InitialCMCTable

class cosmic.sample.initialcmctable.InitialCMCTable(data=None, index: Axes | None = None, columns: Axes | None = None, dtype: Dtype | None = None, copy: bool | None = None)

Bases: DataFrame

classmethod InitialCMCBinaries(index, id1, k1, m1, Reff1, id2, k2, m2, Reff2, a, e)

Create A Table of CMC Binaries

Parameters:
m1float

Primary mass [Msun]

m2float

Secondary mass [Msun]

porbfloat

Orbital period [days]

eccfloat

Eccentricity

kstar1array

0-14 Initial stellar type of the larger object; main sequence stars are 0 if m < 0.7 Msun and 1 otherwise

kstar2array

0-14 Initial stellar type of the smaller object; main sequence stars are 0 if m < 0.7 Msun and 1 otherwise

metallicityfloat

Metallicity of the binaries; Z_sun = 0.02

**kwargs
binfracfloat

System-specific probability of the primary star being in a binary

Returns:
InitialBinariesDataFrame

Single binary initial conditions

classmethod InitialCMCSingles(id_idx, k, m, Reff, r, vr, vt, binind)

Create A Table of CMC Singles

Parameters:
m1float

Primary mass [Msun]

m2float

Secondary mass [Msun]

porbfloat

Orbital period [days]

eccfloat

Eccentricity

kstar1array

0-14 Initial stellar type of the larger object; main sequence stars are 0 if m < 0.7 Msun and 1 otherwise

kstar2array

0-14 Initial stellar type of the smaller object; main sequence stars are 0 if m < 0.7 Msun and 1 otherwise

metallicityfloat

Metallicity of the binaries; Z_sun = 0.02

**kwargs
binfracfloat

System-specific probability of the primary star being in a binary

Returns:
InitialBinariesDataFrame

Single binary initial conditions

ScaleCentralBHMass(Mtotal)

Rescale the central BH mass; needed since this is a class attribute Parameters ———-

Mtotalfloat

total mass of the cluster

classmethod ScaleToNBodyUnits(Singles, Binaries, virial_radius=1, central_bh=0, scale_with_central_bh=False)
Rescale the single masses, radii, and velocities into N-body units
i.e. sum m = M = 1

Kinetic Energy = 0.25 Potential Energy = -0.5

Note that this is already done for r, vr, and vt from the profile generators. However, after the stellar masses are assigned we need to redo it, and the stellar radii and seperations need to be converted from RSUN to code units

Parameters:
SinglesDataFrame

Pandas DataFrame from the InitialCMCSingles function

BinariesDataFrame

Pandas DataFrame from the InitialCMCSingles function

virial_radiusfloat

Virial radius of the cluster in parsec (default 1pc)

Returns:
None: Pandas dataframes are modified in place
__annotations__ = {}
__doc__ = None
__module__ = 'cosmic.sample.initialcmctable'
central_bh = 0.0
mass_of_cluster = None
metallicity = None
classmethod read(filename)

Read Singles and Binaries to HDF5 or FITS file

Parameters:
filename(str)

Must end in “.fits” or “.hdf5/h5”

Returns:
SinglesDataFrame

Pandas DataFrame from the InitialCMCSingles function

BinariesDataFrame

Pandas DataFrame from the InitialCMCBinaries function

classmethod sampler(format_, *args, **kwargs)

Fetch a method to generate an initial binary sample

Parameters:
formatstr

the method name; Choose from ‘independent’ or ‘multidim’

*args

the arguments necessary for the registered sample method; see help(InitialCMCTable.sampler(‘independent’) to see the arguments necessary for the independent sample

The available named formats are:
============== …

Format …

============== …

cmc …

cmc_point_mass …
============== …
scale_with_central_bh = False
scaled_to_nbody_units = False
tidal_radius = None
virial_radius = None
classmethod write(Singles, Binaries, filename='input.hdf5', **kwargs)

Save Singles and Binaries to HDF5 or FITS file

Parameters:
SinglesDataFrame

Pandas DataFrame from the InitialCMCSingles function

BinariesDataFrame

Pandas DataFrame from the InitialCMCBinaries function

filename(str)

Must end in “.fits” or “.hdf5/h5”

Returns:
None:
class cosmic.sample.initialcmctable.Table(data=None, masked=False, names=None, dtype=None, meta=None, copy=True, rows=None, copy_indices=True, units=None, descriptions=None, **kwargs)

Bases: object

A class to represent tables of heterogeneous data.

~astropy.table.Table provides a class for heterogeneous tabular data. A key enhancement provided by the ~astropy.table.Table class over e.g. a numpy structured array is the ability to easily modify the structure of the table by adding or removing columns, or adding new rows of data. In addition table and column metadata are fully supported.

~astropy.table.Table differs from ~astropy.nddata.NDData by the assumption that the input data consists of columns of homogeneous data, where each column has a unique identifier and may contain additional metadata such as the data unit, format, and description.

See also: https://docs.astropy.org/en/stable/table/

Parameters:
datanumpy ndarray, dict, list, table-like object, optional

Data to initialize table.

maskedbool, optional

Specify whether the table is masked.

nameslist, optional

Specify column names.

dtypelist, optional

Specify column data types.

metadict, optional

Metadata associated with the table.

copybool, optional

Copy the input column data and make a deep copy of the input meta. Default is True.

rowsnumpy ndarray, list of list, optional

Row-oriented data for table instead of data argument.

copy_indicesbool, optional

Copy any indices in the input data. Default is True.

unitslist, dict, optional

List or dict of units to apply to columns.

descriptionslist, dict, optional

List or dict of descriptions to apply to columns.

**kwargsdict, optional

Additional keyword args when converting table-like object.

class Column(data=None, name=None, dtype=None, shape=(), length=0, description=None, unit=None, format=None, meta=None, copy=None, copy_indices=True)

Bases: BaseColumn

Define a data column for use in a Table object.

Parameters:
datalist, ndarray, or None

Column data values

namestr

Column name and key for reference within Table

dtype~numpy.dtype-like

Data type for column

shapetuple or ()

Dimensions of a single row element in the column data

lengthint or 0

Number of row elements in column data

descriptionstr or None

Full description of column

unitstr or None

Physical unit

formatstr, None, or callable

Format string for outputting column values. This can be an “old-style” (format % value) or “new-style” (str.format) format specification string or a function or any callable object that accepts a single value and returns a string.

metadict-like or None

Meta-data associated with the column

Examples

A Column can be created in two different ways:

  • Provide a data value but not shape or length (which are inferred from the data).

    Examples:

    col = Column(data=[1, 2], name='name')  # shape=(2,)
    col = Column(data=[[1, 2], [3, 4]], name='name')  # shape=(2, 2)
    col = Column(data=[1, 2], name='name', dtype=float)
    col = Column(data=np.array([1, 2]), name='name')
    col = Column(data=['hello', 'world'], name='name')
    

    The dtype argument can be any value which is an acceptable fixed-size data-type initializer for the numpy.dtype() method. See https://numpy.org/doc/stable/reference/arrays.dtypes.html. Examples include:

    • Python non-string type (float, int, bool)

    • Numpy non-string type (e.g. np.float32, np.int64, np.bool_)

    • Numpy.dtype array-protocol type strings (e.g. ‘i4’, ‘f8’, ‘S15’)

    If no dtype value is provide then the type is inferred using np.array(data).

  • Provide length and optionally shape, but not data

    Examples:

    col = Column(name='name', length=5)
    col = Column(name='name', dtype=int, length=10, shape=(3,4))
    

    The default dtype is np.float64. The shape argument is the array shape of a single cell in the column.

To access the Column data as a raw numpy.ndarray object, you can use one of the data or value attributes (which are equivalent):

col.data
col.value
__bytes__()
__doc__ = 'Define a data column for use in a Table object.\n\n    Parameters\n    ----------\n    data : list, ndarray, or None\n        Column data values\n    name : str\n        Column name and key for reference within Table\n    dtype : `~numpy.dtype`-like\n        Data type for column\n    shape : tuple or ()\n        Dimensions of a single row element in the column data\n    length : int or 0\n        Number of row elements in column data\n    description : str or None\n        Full description of column\n    unit : str or None\n        Physical unit\n    format : str, None, or callable\n        Format string for outputting column values.  This can be an\n        "old-style" (``format % value``) or "new-style" (`str.format`)\n        format specification string or a function or any callable object that\n        accepts a single value and returns a string.\n    meta : dict-like or None\n        Meta-data associated with the column\n\n    Examples\n    --------\n    A Column can be created in two different ways:\n\n    - Provide a ``data`` value but not ``shape`` or ``length`` (which are\n      inferred from the data).\n\n      Examples::\n\n        col = Column(data=[1, 2], name=\'name\')  # shape=(2,)\n        col = Column(data=[[1, 2], [3, 4]], name=\'name\')  # shape=(2, 2)\n        col = Column(data=[1, 2], name=\'name\', dtype=float)\n        col = Column(data=np.array([1, 2]), name=\'name\')\n        col = Column(data=[\'hello\', \'world\'], name=\'name\')\n\n      The ``dtype`` argument can be any value which is an acceptable\n      fixed-size data-type initializer for the numpy.dtype() method.  See\n      `<https://numpy.org/doc/stable/reference/arrays.dtypes.html>`_.\n      Examples include:\n\n      - Python non-string type (float, int, bool)\n      - Numpy non-string type (e.g. np.float32, np.int64, np.bool\\_)\n      - Numpy.dtype array-protocol type strings (e.g. \'i4\', \'f8\', \'S15\')\n\n      If no ``dtype`` value is provide then the type is inferred using\n      ``np.array(data)``.\n\n    - Provide ``length`` and optionally ``shape``, but not ``data``\n\n      Examples::\n\n        col = Column(name=\'name\', length=5)\n        col = Column(name=\'name\', dtype=int, length=10, shape=(3,4))\n\n      The default ``dtype`` is ``np.float64``.  The ``shape`` argument is the\n      array shape of a single cell in the column.\n\n    To access the ``Column`` data as a raw `numpy.ndarray` object, you can use\n    one of the ``data`` or ``value`` attributes (which are equivalent)::\n\n        col.data\n        col.value\n    '
__eq__(other)

Return self==value.

__ge__(other)

Return self>=value.

__gt__(other)

Return self>value.

__hash__ = None
__le__(other)

Return self<=value.

__lt__(other)

Return self<value.

__module__ = 'astropy.table.column'
__ne__(other)

Return self!=value.

static __new__(cls, data=None, name=None, dtype=None, shape=(), length=0, description=None, unit=None, format=None, meta=None, copy=None, copy_indices=True)
__repr__()

Return repr(self).

__setattr__(item, value)

Implement setattr(self, name, value).

__setitem__(index, value)

Set self[key] to value.

__str__()

Return str(self).

_base_repr_(html=False)
_check_string_truncate(value)

Emit a warning if any elements of value will be truncated when value is assigned to self.

_repr_html_()
convert_unit_to(new_unit, equivalencies=[])

Converts the values of the column in-place from the current unit to the given unit.

To change the unit associated with this column without actually changing the data values, simply set the unit property.

Parameters:
new_unitstr or astropy.units.UnitBase instance

The unit to convert to.

equivalencieslist of tuple

A list of equivalence pairs to try if the unit are not directly convertible. See Equivalencies.

Raises:
astropy.units.UnitsError

If units are inconsistent

copy(order='C', data=None, copy_data=True)

Return a copy of the current instance.

If data is supplied then a view (reference) of data is used, and copy_data is ignored.

Parameters:
order{‘C’, ‘F’, ‘A’, ‘K’}, optional

Controls the memory layout of the copy. ‘C’ means C-order, ‘F’ means F-order, ‘A’ means ‘F’ if a is Fortran contiguous, ‘C’ otherwise. ‘K’ means match the layout of a as closely as possible. (Note that this function and :func:numpy.copy are very similar, but have different default values for their order= arguments.) Default is ‘C’.

dataarray, optional

If supplied then use a view of data instead of the instance data. This allows copying the instance attributes and meta.

copy_databool, optional

Make a copy of the internal numpy array instead of using a reference. Default is True.

Returns:
colColumn or MaskedColumn

Copy of the current column (same type as original)

insert(obj, values, axis=0)

Insert values before the given indices in the column and return a new ~astropy.table.Column object.

Parameters:
objint, slice or sequence of int

Object that defines the index or indices before which values is inserted.

valuesarray-like

Value(s) to insert. If the type of values is different from that of the column, values is converted to the matching type. values should be shaped so that it can be broadcast appropriately.

axisint, optional

Axis along which to insert values. If axis is None then the column array is flattened before insertion. Default is 0, which will insert a row.

Returns:
out~astropy.table.Column

A copy of column with values and mask inserted. Note that the insertion does not occur in-place: a new column is returned.

more(max_lines=None, show_name=True, show_unit=False)

Interactively browse column with a paging interface.

Supported keys:

f, <space> : forward one page
b : back one page
r : refresh same page
n : next row
p : previous row
< : go to beginning
> : go to end
q : quit browsing
h : print this help
Parameters:
max_linesint

Maximum number of lines in table output.

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is False.

property name

The name of this column.

pformat(max_lines=None, show_name=True, show_unit=False, show_dtype=False, html=False)

Return a list of formatted string representation of column values.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default will be determined using the astropy.conf.max_lines configuration item. If a negative value of max_lines is supplied then there is no line limit applied.

Parameters:
max_linesint

Maximum lines of output (header + data rows)

show_namebool

Include column name. Default is True.

show_unitbool

Include a header row for unit. Default is False.

show_dtypebool

Include column dtype. Default is False.

htmlbool

Format the output as an HTML table. Default is False.

Returns:
lineslist

List of lines with header and formatted column values

pprint(max_lines=None, show_name=True, show_unit=False, show_dtype=False)

Print a formatted string representation of column values.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default will be determined using the astropy.conf.max_lines configuration item. If a negative value of max_lines is supplied then there is no line limit applied.

Parameters:
max_linesint

Maximum number of values in output

show_namebool

Include column name. Default is True.

show_unitbool

Include a header row for unit. Default is False.

show_dtypebool

Include column dtype. Default is True.

property quantity

A view of this table column as a ~astropy.units.Quantity object with units given by the Column’s unit parameter.

to(unit, equivalencies=[], **kwargs)

Converts this table column to a ~astropy.units.Quantity object with the requested units.

Parameters:
unitunit-like

The unit to convert to (i.e., a valid argument to the astropy.units.Quantity.to() method).

equivalencieslist of tuple

Equivalencies to use for this conversion. See astropy.units.Quantity.to() for more details.

Returns:
quantity~astropy.units.Quantity

A quantity object with the contents of this column in the units unit.

property unit

The unit associated with this column. May be a string or a astropy.units.UnitBase instance.

Setting the unit property does not change the values of the data. To perform a unit conversion, use convert_unit_to.

property ColumnClass
class MaskedColumn(data=None, name=None, mask=None, fill_value=None, dtype=None, shape=(), length=0, description=None, unit=None, format=None, meta=None, copy=None, copy_indices=True)

Bases: Column, _MaskedColumnGetitemShim, MaskedArray

Define a masked data column for use in a Table object.

Parameters:
datalist, ndarray, or None

Column data values

namestr

Column name and key for reference within Table

masklist, ndarray or None

Boolean mask for which True indicates missing or invalid data

fill_valuefloat, int, str, or None

Value used when filling masked column elements

dtype~numpy.dtype-like

Data type for column

shapetuple or ()

Dimensions of a single row element in the column data

lengthint or 0

Number of row elements in column data

descriptionstr or None

Full description of column

unitstr or None

Physical unit

formatstr, None, or callable

Format string for outputting column values. This can be an “old-style” (format % value) or “new-style” (str.format) format specification string or a function or any callable object that accepts a single value and returns a string.

metadict-like or None

Meta-data associated with the column

Examples

A MaskedColumn is similar to a Column except that it includes mask and fill_value attributes. It can be created in two different ways:

  • Provide a data value but not shape or length (which are inferred from the data).

    Examples:

    col = MaskedColumn(data=[1, 2], name='name')
    col = MaskedColumn(data=[1, 2], name='name', mask=[True, False])
    col = MaskedColumn(data=[1, 2], name='name', dtype=float, fill_value=99)
    

    The mask argument will be cast as a boolean array and specifies which elements are considered to be missing or invalid.

    The dtype argument can be any value which is an acceptable fixed-size data-type initializer for the numpy.dtype() method. See https://numpy.org/doc/stable/reference/arrays.dtypes.html. Examples include:

    • Python non-string type (float, int, bool)

    • Numpy non-string type (e.g. np.float32, np.int64, np.bool_)

    • Numpy.dtype array-protocol type strings (e.g. ‘i4’, ‘f8’, ‘S15’)

    If no dtype value is provide then the type is inferred using np.array(data). When data is provided then the shape and length arguments are ignored.

  • Provide length and optionally shape, but not data

    Examples:

    col = MaskedColumn(name='name', length=5)
    col = MaskedColumn(name='name', dtype=int, length=10, shape=(3,4))
    

    The default dtype is np.float64. The shape argument is the array shape of a single cell in the column.

To access the Column data as a raw numpy.ma.MaskedArray object, you can use one of the data or value attributes (which are equivalent):

col.data
col.value
__annotations__ = {}
__doc__ = 'Define a masked data column for use in a Table object.\n\n    Parameters\n    ----------\n    data : list, ndarray, or None\n        Column data values\n    name : str\n        Column name and key for reference within Table\n    mask : list, ndarray or None\n        Boolean mask for which True indicates missing or invalid data\n    fill_value : float, int, str, or None\n        Value used when filling masked column elements\n    dtype : `~numpy.dtype`-like\n        Data type for column\n    shape : tuple or ()\n        Dimensions of a single row element in the column data\n    length : int or 0\n        Number of row elements in column data\n    description : str or None\n        Full description of column\n    unit : str or None\n        Physical unit\n    format : str, None, or callable\n        Format string for outputting column values.  This can be an\n        "old-style" (``format % value``) or "new-style" (`str.format`)\n        format specification string or a function or any callable object that\n        accepts a single value and returns a string.\n    meta : dict-like or None\n        Meta-data associated with the column\n\n    Examples\n    --------\n    A MaskedColumn is similar to a Column except that it includes ``mask`` and\n    ``fill_value`` attributes.  It can be created in two different ways:\n\n    - Provide a ``data`` value but not ``shape`` or ``length`` (which are\n      inferred from the data).\n\n      Examples::\n\n        col = MaskedColumn(data=[1, 2], name=\'name\')\n        col = MaskedColumn(data=[1, 2], name=\'name\', mask=[True, False])\n        col = MaskedColumn(data=[1, 2], name=\'name\', dtype=float, fill_value=99)\n\n      The ``mask`` argument will be cast as a boolean array and specifies\n      which elements are considered to be missing or invalid.\n\n      The ``dtype`` argument can be any value which is an acceptable\n      fixed-size data-type initializer for the numpy.dtype() method.  See\n      `<https://numpy.org/doc/stable/reference/arrays.dtypes.html>`_.\n      Examples include:\n\n      - Python non-string type (float, int, bool)\n      - Numpy non-string type (e.g. np.float32, np.int64, np.bool\\_)\n      - Numpy.dtype array-protocol type strings (e.g. \'i4\', \'f8\', \'S15\')\n\n      If no ``dtype`` value is provide then the type is inferred using\n      ``np.array(data)``.  When ``data`` is provided then the ``shape``\n      and ``length`` arguments are ignored.\n\n    - Provide ``length`` and optionally ``shape``, but not ``data``\n\n      Examples::\n\n        col = MaskedColumn(name=\'name\', length=5)\n        col = MaskedColumn(name=\'name\', dtype=int, length=10, shape=(3,4))\n\n      The default ``dtype`` is ``np.float64``.  The ``shape`` argument is the\n      array shape of a single cell in the column.\n\n    To access the ``Column`` data as a raw `numpy.ma.MaskedArray` object, you can\n    use one of the ``data`` or ``value`` attributes (which are equivalent)::\n\n        col.data\n        col.value\n    '
__module__ = 'astropy.table.column'
static __new__(cls, data=None, name=None, mask=None, fill_value=None, dtype=None, shape=(), length=0, description=None, unit=None, format=None, meta=None, copy=None, copy_indices=True)
__setitem__(index, value)

Set self[key] to value.

_copy_attrs_slice(out)
convert_unit_to(new_unit, equivalencies=[])

Converts the values of the column in-place from the current unit to the given unit.

To change the unit associated with this column without actually changing the data values, simply set the unit property.

Parameters:
new_unitstr or astropy.units.UnitBase instance

The unit to convert to.

equivalencieslist of tuple

A list of equivalence pairs to try if the unit are not directly convertible. See Equivalencies.

Raises:
astropy.units.UnitsError

If units are inconsistent

copy(order='C', data=None, copy_data=True)

Return a copy of the current instance.

If data is supplied then a view (reference) of data is used, and copy_data is ignored.

Parameters:
order{‘C’, ‘F’, ‘A’, ‘K’}, optional

Controls the memory layout of the copy. ‘C’ means C-order, ‘F’ means F-order, ‘A’ means ‘F’ if a is Fortran contiguous, ‘C’ otherwise. ‘K’ means match the layout of a as closely as possible. (Note that this function and :func:numpy.copy are very similar, but have different default values for their order= arguments.) Default is ‘C’.

dataarray, optional

If supplied then use a view of data instead of the instance data. This allows copying the instance attributes and meta.

copy_databool, optional

Make a copy of the internal numpy array instead of using a reference. Default is True.

Returns:
colColumn or MaskedColumn

Copy of the current column (same type as original)

property data

The plain MaskedArray data held by this column.

property fill_value

The filling value of the masked array is a scalar. When setting, None will set to a default based on the data type.

Examples

>>> for dt in [np.int32, np.int64, np.float64, np.complex128]:
...     np.ma.array([0, 1], dtype=dt).get_fill_value()
...
np.int64(999999)
np.int64(999999)
np.float64(1e+20)
np.complex128(1e+20+0j)
>>> x = np.ma.array([0, 1.], fill_value=-np.inf)
>>> x.fill_value
np.float64(-inf)
>>> x.fill_value = np.pi
>>> x.fill_value
np.float64(3.1415926535897931)

Reset to default:

>>> x.fill_value = None
>>> x.fill_value
np.float64(1e+20)
filled(fill_value=None)

Return a copy of self, with masked values filled with a given value.

Parameters:
fill_valuescalar; optional

The value to use for invalid entries (None by default). If None, the fill_value attribute of the array is used instead.

Returns:
filled_columnColumn

A copy of self with masked entries replaced by fill_value (be it the function argument or the attribute of self).

info

Container for meta information like name, description, format.

This is required when the object is used as a mixin column within a table, but can be used as a general way to store meta information. In this case it just adds the mask_val attribute.

insert(obj, values, mask=None, axis=0)

Insert values along the given axis before the given indices and return a new ~astropy.table.MaskedColumn object.

Parameters:
objint, slice or sequence of int

Object that defines the index or indices before which values is inserted.

valuesarray-like

Value(s) to insert. If the type of values is different from that of the column, values is converted to the matching type. values should be shaped so that it can be broadcast appropriately.

maskbool or array-like

Mask value(s) to insert. If not supplied, and values does not have a mask either, then False is used.

axisint, optional

Axis along which to insert values. If axis is None then the column array is flattened before insertion. Default is 0, which will insert a row.

Returns:
out~astropy.table.MaskedColumn

A copy of column with values and mask inserted. Note that the insertion does not occur in-place: a new masked column is returned.

more(max_lines=None, show_name=True, show_unit=False)

Interactively browse column with a paging interface.

Supported keys:

f, <space> : forward one page
b : back one page
r : refresh same page
n : next row
p : previous row
< : go to beginning
> : go to end
q : quit browsing
h : print this help
Parameters:
max_linesint

Maximum number of lines in table output.

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is False.

property name

The name of this column.

pformat(max_lines=None, show_name=True, show_unit=False, show_dtype=False, html=False)

Return a list of formatted string representation of column values.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default will be determined using the astropy.conf.max_lines configuration item. If a negative value of max_lines is supplied then there is no line limit applied.

Parameters:
max_linesint

Maximum lines of output (header + data rows)

show_namebool

Include column name. Default is True.

show_unitbool

Include a header row for unit. Default is False.

show_dtypebool

Include column dtype. Default is False.

htmlbool

Format the output as an HTML table. Default is False.

Returns:
lineslist

List of lines with header and formatted column values

pprint(max_lines=None, show_name=True, show_unit=False, show_dtype=False)

Print a formatted string representation of column values.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default will be determined using the astropy.conf.max_lines configuration item. If a negative value of max_lines is supplied then there is no line limit applied.

Parameters:
max_linesint

Maximum number of values in output

show_namebool

Include column name. Default is True.

show_unitbool

Include a header row for unit. Default is False.

show_dtypebool

Include column dtype. Default is True.

class Row(table, index)

Bases: object

A class to represent one row of a Table object.

A Row object is returned when a Table object is indexed with an integer or when iterating over a table:

>>> from astropy.table import Table
>>> table = Table([(1, 2), (3, 4)], names=('a', 'b'),
...               dtype=('int32', 'int32'))
>>> row = table[1]
>>> row
<Row index=1>
  a     b
int32 int32
----- -----
    2     4
>>> row['a']
2
>>> row[1]
4
__array__(dtype=None, copy=None)

Support converting Row to np.array via np.array(table).

Coercion to a different dtype via np.array(table, dtype) is not supported and will raise a ValueError.

If the parent table is masked then the mask information is dropped.

__bytes__()
__dict__ = mappingproxy({'__module__': 'astropy.table.row', '__doc__': "A class to represent one row of a Table object.\n\n    A Row object is returned when a Table object is indexed with an integer\n    or when iterating over a table::\n\n      >>> from astropy.table import Table\n      >>> table = Table([(1, 2), (3, 4)], names=('a', 'b'),\n      ...               dtype=('int32', 'int32'))\n      >>> row = table[1]\n      >>> row\n      <Row index=1>\n        a     b\n      int32 int32\n      ----- -----\n          2     4\n      >>> row['a']\n      2\n      >>> row[1]\n      4\n    ", '__init__': <function Row.__init__>, '__getitem__': <function Row.__getitem__>, '__setitem__': <function Row.__setitem__>, '_ipython_key_completions_': <function Row._ipython_key_completions_>, '__eq__': <function Row.__eq__>, '__ne__': <function Row.__ne__>, '__array__': <function Row.__array__>, '__len__': <function Row.__len__>, '__iter__': <function Row.__iter__>, 'get': <function Row.get>, 'keys': <function Row.keys>, 'values': <function Row.values>, 'table': <property object>, 'index': <property object>, 'as_void': <function Row.as_void>, 'meta': <property object>, 'columns': <property object>, 'colnames': <property object>, 'dtype': <property object>, '_base_repr_': <function Row._base_repr_>, '_repr_html_': <function Row._repr_html_>, '__repr__': <function Row.__repr__>, '__str__': <function Row.__str__>, '__bytes__': <function Row.__bytes__>, '__dict__': <attribute '__dict__' of 'Row' objects>, '__weakref__': <attribute '__weakref__' of 'Row' objects>, '__hash__': None, '__annotations__': {}})
__doc__ = "A class to represent one row of a Table object.\n\n    A Row object is returned when a Table object is indexed with an integer\n    or when iterating over a table::\n\n      >>> from astropy.table import Table\n      >>> table = Table([(1, 2), (3, 4)], names=('a', 'b'),\n      ...               dtype=('int32', 'int32'))\n      >>> row = table[1]\n      >>> row\n      <Row index=1>\n        a     b\n      int32 int32\n      ----- -----\n          2     4\n      >>> row['a']\n      2\n      >>> row[1]\n      4\n    "
__eq__(other)

Return self==value.

__getitem__(item)
__hash__ = None
__init__(table, index)
__iter__()
__len__()
__module__ = 'astropy.table.row'
__ne__(other)

Return self!=value.

__repr__()

Return repr(self).

__setitem__(item, val)
__str__()

Return str(self).

__weakref__

list of weak references to the object (if defined)

_base_repr_(html=False)

Display row as a single-line table but with appropriate header line.

_ipython_key_completions_()
_repr_html_()
as_void()

Returns a read-only copy of the row values in the form of np.void or np.ma.mvoid objects. This corresponds to the object types returned for row indexing of a pure numpy structured array or masked array. This method is slow and its use is discouraged when possible.

Returns:
void_rownumpy.void or numpy.ma.mvoid

Copy of row values. numpy.void if unmasked, numpy.ma.mvoid else.

property colnames
property columns
property dtype
get(key, default=None, /)

Return the value for key if key is in the columns, else default.

Parameters:
keystr, positional-only

The name of the column to look for.

defaultobject, optional, positional-only

The value to return if the key is not among the columns.

Returns:
object

The value in the key column of the row if present, default otherwise.

Examples

>>> from astropy.table import Table
>>> t = Table({"a": [2, 3, 5], "b": [7, 11, 13]})
>>> t[0].get("a")
2
>>> t[1].get("b", 0)
11
>>> t[2].get("c", 0)
0
property index
keys()
property meta
property table
values()
class TableColumns(cols={})

Bases: OrderedDict

OrderedDict subclass for a set of columns.

This class enhances item access to provide convenient access to columns by name or index, including slice access. It also handles renaming of columns.

The initialization argument cols can be a list of Column objects or any structure that is valid for initializing a Python dict. This includes a dict, list of (key, val) tuples or [key, val] lists, etc.

Parameters:
colsdict, list, tuple; optional

Column objects as data structure that can init dict (see above)

__delitem__(name)

Delete self[key].

__doc__ = 'OrderedDict subclass for a set of columns.\n\n    This class enhances item access to provide convenient access to columns\n    by name or index, including slice access.  It also handles renaming\n    of columns.\n\n    The initialization argument ``cols`` can be a list of ``Column`` objects\n    or any structure that is valid for initializing a Python dict.  This\n    includes a dict, list of (key, val) tuples or [key, val] lists, etc.\n\n    Parameters\n    ----------\n    cols : dict, list, tuple; optional\n        Column objects as data structure that can init dict (see above)\n    '
__getitem__(item)

Get items from a TableColumns object.

tc = TableColumns(cols=[Column(name='a'), Column(name='b'), Column(name='c')])
tc['a']  # Column('a')
tc[1] # Column('b')
tc['a', 'b'] # <TableColumns names=('a', 'b')>
tc[1:3] # <TableColumns names=('b', 'c')>
__init__(cols={})
__module__ = 'astropy.table.table'
__repr__()

Return repr(self).

__setitem__(item, value, validated=False)

Set item in this dict instance, but do not allow directly replacing an existing column unless it is already validated (and thus is certain to not corrupt the table).

NOTE: it is easily possible to corrupt a table by directly adding a new key to the TableColumns attribute of a Table, e.g. t.columns['jane'] = 'doe'.

_rename_column(name, new_name)
isinstance(cls)

Return a list of columns which are instances of the specified classes.

Parameters:
clsclass or tuple thereof

Column class (including mixin) or tuple of Column classes.

Returns:
col_listlist of Column

List of Column objects which are instances of given classes.

not_isinstance(cls)

Return a list of columns which are not instances of the specified classes.

Parameters:
clsclass or tuple thereof

Column class (including mixin) or tuple of Column classes.

Returns:
col_listlist of Column

List of Column objects which are not instances of given classes.

setdefault(key, default)

Deprecated since version 6.1: The t.columns.setdefault() function is deprecated and may be removed in a future version. Use t.setdefault() instead.

update(*args, **kwargs)

Deprecated since version 6.1: The t.columns.update() function is deprecated and may be removed in a future version. Use t.update() instead.

class TableFormatter

Bases: object

__dict__ = mappingproxy({'__module__': 'astropy.table.pprint', '_get_pprint_size': <staticmethod(<function TableFormatter._get_pprint_size>)>, '_pformat_col': <function TableFormatter._pformat_col>, '_name_and_structure': <function TableFormatter._name_and_structure>, '_pformat_col_iter': <function TableFormatter._pformat_col_iter>, '_pformat_table': <function TableFormatter._pformat_table>, '_more_tabcol': <function TableFormatter._more_tabcol>, '__dict__': <attribute '__dict__' of 'TableFormatter' objects>, '__weakref__': <attribute '__weakref__' of 'TableFormatter' objects>, '__doc__': None, '__annotations__': {}})
__doc__ = None
__module__ = 'astropy.table.pprint'
__weakref__

list of weak references to the object (if defined)

static _get_pprint_size(max_lines=None, max_width=None)

Get the output size (number of lines and character width) for Column and Table pformat/pprint methods.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default will be determined using the astropy.table.conf.max_lines configuration item. If a negative value of max_lines is supplied then there is no line limit applied.

The same applies for max_width except the configuration item is astropy.table.conf.max_width.

Parameters:
max_linesint or None

Maximum lines of output (header + data rows)

max_widthint or None

Maximum width (characters) output

Returns:
max_lines, max_widthint
_more_tabcol(tabcol, max_lines=None, max_width=None, show_name=True, show_unit=None, show_dtype=False)

Interactive “more” of a table or column.

Parameters:
max_linesint or None

Maximum number of rows to output

max_widthint or None

Maximum character width of output

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is False.

_name_and_structure(name, dtype, sep=' ')

Format a column name, including a possible structure.

Normally, just returns the name, but if it has a structured dtype, will add the parts in between square brackets. E.g., “name [f0, f1]” or “name [f0[sf0, sf1], f1]”.

_pformat_col(col, max_lines=None, show_name=True, show_unit=None, show_dtype=False, show_length=None, html=False, align=None)

Return a list of formatted string representation of column values.

Parameters:
max_linesint

Maximum lines of output (header + data rows)

show_namebool

Include column name. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include column dtype. Default is False.

show_lengthbool

Include column length at end. Default is to show this only if the column is not shown completely.

htmlbool

Output column as HTML

alignstr

Left/right alignment of columns. Default is ‘>’ (right) for all columns. Other allowed values are ‘<’, ‘^’, and ‘0=’ for left, centered, and 0-padded, respectively.

Returns:
lineslist

List of lines with formatted column values

outsdict

Dict which is used to pass back additional values defined within the iterator.

_pformat_col_iter(col, max_lines, show_name, show_unit, outs, show_dtype=False, show_length=None)

Iterator which yields formatted string representation of column values.

Parameters:
max_linesint

Maximum lines of output (header + data rows)

show_namebool

Include column name. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

outsdict

Must be a dict which is used to pass back additional values defined within the iterator.

show_dtypebool

Include column dtype. Default is False.

show_lengthbool

Include column length at end. Default is to show this only if the column is not shown completely.

_pformat_table(table, max_lines=None, max_width=None, show_name=True, show_unit=None, show_dtype=False, html=False, tableid=None, tableclass=None, align=None)

Return a list of lines for the formatted string representation of the table.

Parameters:
max_linesint or None

Maximum number of rows to output

max_widthint or None

Maximum character width of output

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is to False.

htmlbool

Format the output as an HTML table. Default is False.

tableidstr or None

An ID tag for the table; only used if html is set. Default is “table{id}”, where id is the unique integer id of the table object, id(table)

tableclassstr or list of str or None

CSS classes for the table; only used if html is set. Default is none

alignstr or list or tuple

Left/right alignment of columns. Default is ‘>’ (right) for all columns. Other allowed values are ‘<’, ‘^’, and ‘0=’ for left, centered, and 0-padded, respectively. A list of strings can be provided for alignment of tables with multiple columns.

Returns:
rowslist

Formatted table as a list of strings

outsdict

Dict which is used to pass back additional values defined within the iterator.

__array__(dtype=None, copy=None)

Support converting Table to np.array via np.array(table).

Coercion to a different dtype via np.array(table, dtype) is not supported and will raise a ValueError.

__bytes__()
__copy__()
__deepcopy__(memo=None)
__delitem__(item)
__dict__ = mappingproxy({'__module__': 'astropy.table.table', '__doc__': 'A class to represent tables of heterogeneous data.\n\n    `~astropy.table.Table` provides a class for heterogeneous tabular data.\n    A key enhancement provided by the `~astropy.table.Table` class over\n    e.g. a `numpy` structured array is the ability to easily modify the\n    structure of the table by adding or removing columns, or adding new\n    rows of data.  In addition table and column metadata are fully supported.\n\n    `~astropy.table.Table` differs from `~astropy.nddata.NDData` by the\n    assumption that the input data consists of columns of homogeneous data,\n    where each column has a unique identifier and may contain additional\n    metadata such as the data unit, format, and description.\n\n    See also: https://docs.astropy.org/en/stable/table/\n\n    Parameters\n    ----------\n    data : numpy ndarray, dict, list, table-like object, optional\n        Data to initialize table.\n    masked : bool, optional\n        Specify whether the table is masked.\n    names : list, optional\n        Specify column names.\n    dtype : list, optional\n        Specify column data types.\n    meta : dict, optional\n        Metadata associated with the table.\n    copy : bool, optional\n        Copy the input column data and make a deep copy of the input meta.\n        Default is True.\n    rows : numpy ndarray, list of list, optional\n        Row-oriented data for table instead of ``data`` argument.\n    copy_indices : bool, optional\n        Copy any indices in the input data. Default is True.\n    units : list, dict, optional\n        List or dict of units to apply to columns.\n    descriptions : list, dict, optional\n        List or dict of descriptions to apply to columns.\n    **kwargs : dict, optional\n        Additional keyword args when converting table-like object.\n    ', 'meta': <astropy.utils.metadata.core.MetaData object>, 'Row': <class 'astropy.table.row.Row'>, 'Column': <class 'astropy.table.column.Column'>, 'MaskedColumn': <class 'astropy.table.column.MaskedColumn'>, 'TableColumns': <class 'astropy.table.table.TableColumns'>, 'TableFormatter': <class 'astropy.table.pprint.TableFormatter'>, 'read': <astropy.io.registry.interface.UnifiedReadWriteMethod object>, 'write': <astropy.io.registry.interface.UnifiedReadWriteMethod object>, 'pprint_exclude_names': <PprintIncludeExclude name=pprint_exclude_names default=None>, 'pprint_include_names': <PprintIncludeExclude name=pprint_include_names default=None>, 'as_array': <function Table.as_array>, '__init__': <function Table.__init__>, '_set_column_attribute': <function Table._set_column_attribute>, '__getstate__': <function Table.__getstate__>, '__setstate__': <function Table.__setstate__>, 'mask': <property object>, '_mask': <property object>, 'filled': <function Table.filled>, 'indices': <property object>, 'loc': <property object>, 'loc_indices': <property object>, 'iloc': <property object>, 'add_index': <function Table.add_index>, 'remove_indices': <function Table.remove_indices>, 'index_mode': <function Table.index_mode>, '__array__': <function Table.__array__>, '_check_names_dtype': <function Table._check_names_dtype>, '_init_from_list_of_dicts': <function Table._init_from_list_of_dicts>, '_init_from_list': <function Table._init_from_list>, '_convert_data_to_col': <function Table._convert_data_to_col>, '_init_from_ndarray': <function Table._init_from_ndarray>, '_init_from_dict': <function Table._init_from_dict>, '_get_col_cls_for_table': <function Table._get_col_cls_for_table>, '_convert_col_for_table': <function Table._convert_col_for_table>, '_init_from_cols': <function Table._init_from_cols>, '_new_from_slice': <function Table._new_from_slice>, '_make_table_from_cols': <staticmethod(<function Table._make_table_from_cols>)>, '_set_col_parent_table_and_mask': <function Table._set_col_parent_table_and_mask>, 'itercols': <function Table.itercols>, '_base_repr_': <function Table._base_repr_>, '_repr_html_': <function Table._repr_html_>, '__repr__': <function Table.__repr__>, '__str__': <function Table.__str__>, '__bytes__': <function Table.__bytes__>, 'has_mixin_columns': <property object>, 'has_masked_columns': <property object>, 'has_masked_values': <property object>, '_is_mixin_for_table': <function Table._is_mixin_for_table>, 'pprint': <function Table.pprint>, 'pprint_all': <function Table.pprint_all>, '_make_index_row_display_table': <function Table._make_index_row_display_table>, 'show_in_notebook': <function Table.show_in_notebook>, 'show_in_browser': <function Table.show_in_browser>, 'pformat': <function Table.pformat>, 'pformat_all': <function Table.pformat_all>, 'more': <function Table.more>, '__getitem__': <function Table.__getitem__>, '__setitem__': <function Table.__setitem__>, '__delitem__': <function Table.__delitem__>, '_ipython_key_completions_': <function Table._ipython_key_completions_>, 'field': <function Table.field>, 'masked': <property object>, '_set_masked': <function Table._set_masked>, 'ColumnClass': <property object>, 'dtype': <property object>, 'colnames': <property object>, '_is_list_or_tuple_of_str': <staticmethod(<function Table._is_list_or_tuple_of_str>)>, 'keys': <function Table.keys>, 'values': <function Table.values>, 'items': <function Table.items>, '__len__': <function Table.__len__>, '__or__': <function Table.__or__>, '__ior__': <function Table.__ior__>, 'index_column': <function Table.index_column>, 'add_column': <function Table.add_column>, 'add_columns': <function Table.add_columns>, '_replace_column_warnings': <function Table._replace_column_warnings>, 'replace_column': <function Table.replace_column>, 'remove_row': <function Table.remove_row>, 'remove_rows': <function Table.remove_rows>, 'iterrows': <function Table.iterrows>, '_set_of_names_in_colnames': <function Table._set_of_names_in_colnames>, 'remove_column': <function Table.remove_column>, 'remove_columns': <function Table.remove_columns>, '_convert_string_dtype': <function Table._convert_string_dtype>, 'convert_bytestring_to_unicode': <function Table.convert_bytestring_to_unicode>, 'convert_unicode_to_bytestring': <function Table.convert_unicode_to_bytestring>, 'keep_columns': <function Table.keep_columns>, 'rename_column': <function Table.rename_column>, 'rename_columns': <function Table.rename_columns>, '_set_row': <function Table._set_row>, 'add_row': <function Table.add_row>, 'insert_row': <function Table.insert_row>, '_replace_cols': <function Table._replace_cols>, 'setdefault': <function Table.setdefault>, 'update': <function Table.update>, 'argsort': <function Table.argsort>, 'sort': <function Table.sort>, 'reverse': <function Table.reverse>, 'round': <function Table.round>, 'copy': <function Table.copy>, '__deepcopy__': <function Table.__deepcopy__>, '__copy__': <function Table.__copy__>, '__eq__': <function Table.__eq__>, '__ne__': <function Table.__ne__>, '_rows_equal': <function Table._rows_equal>, 'values_equal': <function Table.values_equal>, 'groups': <property object>, 'group_by': <function Table.group_by>, 'to_pandas': <function Table.to_pandas>, 'from_pandas': <classmethod(<function Table.from_pandas>)>, 'info': <astropy.table.info.TableInfo object>, '__dict__': <attribute '__dict__' of 'Table' objects>, '__weakref__': <attribute '__weakref__' of 'Table' objects>, '__hash__': None, '__annotations__': {}})
__doc__ = 'A class to represent tables of heterogeneous data.\n\n    `~astropy.table.Table` provides a class for heterogeneous tabular data.\n    A key enhancement provided by the `~astropy.table.Table` class over\n    e.g. a `numpy` structured array is the ability to easily modify the\n    structure of the table by adding or removing columns, or adding new\n    rows of data.  In addition table and column metadata are fully supported.\n\n    `~astropy.table.Table` differs from `~astropy.nddata.NDData` by the\n    assumption that the input data consists of columns of homogeneous data,\n    where each column has a unique identifier and may contain additional\n    metadata such as the data unit, format, and description.\n\n    See also: https://docs.astropy.org/en/stable/table/\n\n    Parameters\n    ----------\n    data : numpy ndarray, dict, list, table-like object, optional\n        Data to initialize table.\n    masked : bool, optional\n        Specify whether the table is masked.\n    names : list, optional\n        Specify column names.\n    dtype : list, optional\n        Specify column data types.\n    meta : dict, optional\n        Metadata associated with the table.\n    copy : bool, optional\n        Copy the input column data and make a deep copy of the input meta.\n        Default is True.\n    rows : numpy ndarray, list of list, optional\n        Row-oriented data for table instead of ``data`` argument.\n    copy_indices : bool, optional\n        Copy any indices in the input data. Default is True.\n    units : list, dict, optional\n        List or dict of units to apply to columns.\n    descriptions : list, dict, optional\n        List or dict of descriptions to apply to columns.\n    **kwargs : dict, optional\n        Additional keyword args when converting table-like object.\n    '
__eq__(other)

Return self==value.

__getitem__(item)
__getstate__()
__hash__ = None
__init__(data=None, masked=False, names=None, dtype=None, meta=None, copy=True, rows=None, copy_indices=True, units=None, descriptions=None, **kwargs)
__ior__(other)
__len__()
__module__ = 'astropy.table.table'
__ne__(other)

Return self!=value.

__or__(other)

Return self|value.

__repr__()

Return repr(self).

__setitem__(item, value)
__setstate__(state)
__str__()

Return str(self).

__weakref__

list of weak references to the object (if defined)

_base_repr_(html=False, descr_vals=None, max_width=None, tableid=None, show_dtype=True, max_lines=None, tableclass=None)
_check_names_dtype(names, dtype, n_cols)

Make sure that names and dtype are both iterable and have the same length as data.

_convert_col_for_table(col)

Make sure that all Column objects have correct base class for this type of Table. For a base Table this most commonly means setting to MaskedColumn if the table is masked. Table subclasses like QTable override this method.

_convert_data_to_col(data, copy=True, default_name=None, dtype=None, name=None)

Convert any allowed sequence data col to a column object that can be used directly in the self.columns dict. This could be a Column, MaskedColumn, or mixin column.

The final column name is determined by:

name or data.info.name or def_name

If data has no info then name = name or def_name.

The behavior of copy for Column objects is: - copy=True: new class instance with a copy of data and deep copy of meta - copy=False: new class instance with same data and a key-only copy of meta

For mixin columns: - copy=True: new class instance with copy of data and deep copy of meta - copy=False: original instance (no copy at all)

Parameters:
dataobject (column-like sequence)

Input column data

copybool

Make a copy

default_namestr

Default name

dtypenp.dtype or None

Data dtype

namestr or None

Column name

Returns:
colColumn, MaskedColumn, mixin-column type

Object that can be used as a column in self

_convert_string_dtype(in_kind, out_kind, encode_decode_func)

Convert string-like columns to/from bytestring and unicode (internal only).

Parameters:
in_kindstr

Input dtype.kind

out_kindstr

Output dtype.kind

_get_col_cls_for_table(col)

Get the correct column class to use for upgrading any Column-like object.

For a masked table, ensure any Column-like object is a subclass of the table MaskedColumn.

For unmasked table, ensure any MaskedColumn-like object is a subclass of the table MaskedColumn. If not a MaskedColumn, then ensure that any Column-like object is a subclass of the table Column.

_init_from_cols(cols)

Initialize table from a list of Column or mixin objects.

_init_from_dict(data, names, dtype, n_cols, copy)

Initialize table from a dictionary of columns.

_init_from_list(data, names, dtype, n_cols, copy)

Initialize table from a list of column data. A column can be a Column object, np.ndarray, mixin, or any other iterable object.

_init_from_list_of_dicts(data, names, dtype, n_cols, copy)

Initialize table from a list of dictionaries representing rows.

_init_from_ndarray(data, names, dtype, n_cols, copy)

Initialize table from an ndarray structured array.

_ipython_key_completions_()
static _is_list_or_tuple_of_str(names)

Check that names is a tuple or list of strings.

_is_mixin_for_table(col)

Determine if col should be added to the table directly as a mixin column.

_make_index_row_display_table(index_row_name)
static _make_table_from_cols(table, cols, verify=True, names=None)

Make table in-place so that it represents the given list of cols.

property _mask

This is needed so that comparison of a masked Table and a MaskedArray works. The requirement comes from numpy.ma.core so don’t remove this property.

_new_from_slice(slice_)

Create a new table as a referenced slice from self.

_replace_cols(columns)
_replace_column_warnings(name, col)

Same as replace_column but issues warnings under various circumstances.

_repr_html_()
_rows_equal(other)

Row-wise comparison of table with any other object.

This is actual implementation for __eq__.

Returns a 1-D boolean numpy array showing result of row-wise comparison, or a bool (False) in cases where comparison isn’t possible (uncomparable dtypes or unbroadcastable shapes). Intended to follow legacy numpy’s elementwise comparison rules.

This is the same as the == comparison for tables.

Parameters:
otherTable or DataFrame or ndarray

An object to compare with table

Examples

Comparing one Table with other:

>>> t1 = Table([[1,2],[4,5],[7,8]], names=('a','b','c'))
>>> t2 = Table([[1,2],[4,5],[7,8]], names=('a','b','c'))
>>> t1._rows_equal(t2)
array([ True,  True])
_set_col_parent_table_and_mask(col)

Set col.parent_table = self and force col to have mask attribute if the table is masked and col.mask does not exist.

_set_column_attribute(attr, values)

Set attr for columns to values, which can be either a dict (keyed by column name) or a dict of name: value pairs. This is used for handling the units and descriptions kwargs to __init__.

_set_masked(masked)

Set the table masked property.

Parameters:
maskedbool

State of table masking (True or False)

_set_of_names_in_colnames(names)

Return names as a set if valid, or raise a KeyError.

names is valid if all elements in it are in self.colnames. If names is a string then it is interpreted as a single column name.

_set_row(idx, colnames, vals)
add_column(col, index=None, name=None, rename_duplicate=False, copy=True, default_name=None)

Add a new column to the table using col as input. If index is supplied then insert column before index position in the list of columns, otherwise append column to the end of the list.

The col input can be any data object which is acceptable as a ~astropy.table.Table column object or can be converted. This includes mixin columns and scalar or length=1 objects which get broadcast to match the table length.

To add several columns at once use add_columns() or simply call add_column() for each one. There is very little performance difference in the two approaches.

Parameters:
colobject

Data object for the new column

indexint or None

Insert column before this position or at end (default).

namestr

Column name

rename_duplicatebool

Uniquify column name if it already exist. Default is False.

copybool

Make a copy of the new column. Default is True.

default_namestr or None

Name to use if both name and col.info.name are not available. Defaults to col{number_of_columns}.

Examples

Create a table with two columns ‘a’ and ‘b’, then create a third column ‘c’ and append it to the end of the table:

>>> t = Table([[1, 2], [0.1, 0.2]], names=('a', 'b'))
>>> col_c = Column(name='c', data=['x', 'y'])
>>> t.add_column(col_c)
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y

Add column ‘d’ at position 1. Note that the column is inserted before the given index:

>>> t.add_column(['a', 'b'], name='d', index=1)
>>> print(t)
 a   d   b   c
--- --- --- ---
  1   a 0.1   x
  2   b 0.2   y

Add second column named ‘b’ with rename_duplicate:

>>> t = Table([[1, 2], [0.1, 0.2]], names=('a', 'b'))
>>> t.add_column(1.1, name='b', rename_duplicate=True)
>>> print(t)
 a   b  b_1
--- --- ---
  1 0.1 1.1
  2 0.2 1.1

Add an unnamed column or mixin object in the table using a default name or by specifying an explicit name with name. Name can also be overridden:

>>> t = Table([[1, 2], [0.1, 0.2]], names=('a', 'b'))
>>> t.add_column(['a', 'b'])
>>> t.add_column(col_c, name='d')
>>> print(t)
 a   b  col2  d
--- --- ---- ---
  1 0.1    a   x
  2 0.2    b   y
add_columns(cols, indexes=None, names=None, copy=True, rename_duplicate=False)

Add a list of new columns the table using cols data objects. If a corresponding list of indexes is supplied then insert column before each index position in the original list of columns, otherwise append columns to the end of the list.

The cols input can include any data objects which are acceptable as ~astropy.table.Table column objects or can be converted. This includes mixin columns and scalar or length=1 objects which get broadcast to match the table length.

From a performance perspective there is little difference between calling this method once or looping over the new columns and calling add_column() for each column.

Parameters:
colslist of object

List of data objects for the new columns

indexeslist of int or None

Insert column before this position or at end (default).

nameslist of str

Column names

copybool

Make a copy of the new columns. Default is True.

rename_duplicatebool

Uniquify new column names if they duplicate the existing ones. Default is False.

Examples

Create a table with two columns ‘a’ and ‘b’, then create columns ‘c’ and ‘d’ and append them to the end of the table:

>>> t = Table([[1, 2], [0.1, 0.2]], names=('a', 'b'))
>>> col_c = Column(name='c', data=['x', 'y'])
>>> col_d = Column(name='d', data=['u', 'v'])
>>> t.add_columns([col_c, col_d])
>>> print(t)
 a   b   c   d
--- --- --- ---
  1 0.1   x   u
  2 0.2   y   v

Add column ‘c’ at position 0 and column ‘d’ at position 1. Note that the columns are inserted before the given position:

>>> t = Table([[1, 2], [0.1, 0.2]], names=('a', 'b'))
>>> t.add_columns([['x', 'y'], ['u', 'v']], names=['c', 'd'],
...               indexes=[0, 1])
>>> print(t)
 c   a   d   b
--- --- --- ---
  x   1   u 0.1
  y   2   v 0.2

Add second column ‘b’ and column ‘c’ with rename_duplicate:

>>> t = Table([[1, 2], [0.1, 0.2]], names=('a', 'b'))
>>> t.add_columns([[1.1, 1.2], ['x', 'y']], names=('b', 'c'),
...               rename_duplicate=True)
>>> print(t)
 a   b  b_1  c
--- --- --- ---
  1 0.1 1.1  x
  2 0.2 1.2  y

Add unnamed columns or mixin objects in the table using default names or by specifying explicit names with names. Names can also be overridden:

>>> t = Table()
>>> col_b = Column(name='b', data=['u', 'v'])
>>> t.add_columns([[1, 2], col_b])
>>> t.add_columns([[3, 4], col_b], names=['c', 'd'])
>>> print(t)
col0  b   c   d
---- --- --- ---
   1   u   3   u
   2   v   4   v
add_index(colnames, engine=None, unique=False)

Insert a new index among one or more columns. If there are no indices, make this index the primary table index.

Parameters:
colnamesstr or list

List of column names (or a single column name) to index

enginetype or None

Indexing engine class to use, either ~astropy.table.SortedArray, ~astropy.table.BST, or ~astropy.table.SCEngine. If the supplied argument is None (by default), use ~astropy.table.SortedArray.

uniquebool

Whether the values of the index must be unique. Default is False.

add_row(vals=None, mask=None)

Add a new row to the end of the table.

The vals argument can be:

sequence (e.g. tuple or list)

Column values in the same order as table columns.

mapping (e.g. dict)

Keys corresponding to column names. Missing values will be filled with np.zeros for the column dtype.

None

All values filled with np.zeros for the column dtype.

This method requires that the Table object “owns” the underlying array data. In particular one cannot add a row to a Table that was initialized with copy=False from an existing array.

The mask attribute should give (if desired) the mask for the values. The type of the mask should match that of the values, i.e. if vals is an iterable, then mask should also be an iterable with the same length, and if vals is a mapping, then mask should be a dictionary.

Parameters:
valstuple, list, dict or None

Use the specified values in the new row

masktuple, list, dict or None

Use the specified mask values in the new row

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1,2],[4,5],[7,8]], names=('a','b','c'))
>>> print(t)
 a   b   c
--- --- ---
  1   4   7
  2   5   8

Adding a new row with entries ‘3’ in ‘a’, ‘6’ in ‘b’ and ‘9’ in ‘c’:

>>> t.add_row([3,6,9])
>>> print(t)
  a   b   c
  --- --- ---
  1   4   7
  2   5   8
  3   6   9
argsort(keys=None, kind=None, reverse=False)

Return the indices which would sort the table according to one or more key columns. This simply calls the numpy.argsort function on the table with the order parameter set to keys.

Parameters:
keysstr or list of str

The column name(s) to order the table by

kind{‘quicksort’, ‘mergesort’, ‘heapsort’, ‘stable’}, optional

Sorting algorithm used by numpy.argsort.

reversebool

Sort in reverse order (default=False)

Returns:
index_arrayndarray, int

Array of indices that sorts the table by the specified key column(s).

as_array(keep_byteorder=False, names=None)

Return a new copy of the table in the form of a structured np.ndarray or np.ma.MaskedArray object (as appropriate).

Parameters:
keep_byteorderbool, optional

By default the returned array has all columns in native byte order. However, if this option is True this preserves the byte order of all columns (if any are non-native).

nameslist, optional:

List of column names to include for returned structured array. Default is to include all table columns.

Returns:
table_arrayarray or ~numpy.ma.MaskedArray

Copy of table as a numpy structured array. ndarray for unmasked or ~numpy.ma.MaskedArray for masked.

property colnames
convert_bytestring_to_unicode()

Convert bytestring columns (dtype.kind=’S’) to unicode (dtype.kind=’U’) using UTF-8 encoding.

Internally this changes string columns to represent each character in the string with a 4-byte UCS-4 equivalent, so it is inefficient for memory but allows scripts to manipulate string arrays with natural syntax.

convert_unicode_to_bytestring()

Convert unicode columns (dtype.kind=’U’) to bytestring (dtype.kind=’S’) using UTF-8 encoding.

When exporting a unicode string array to a file, it may be desirable to encode unicode columns as bytestrings.

copy(copy_data=True)

Return a copy of the table.

Parameters:
copy_databool

If True (the default), copy the underlying data array and make a deep copy of the meta attribute. Otherwise, use the same data array and make a shallow (key-only) copy of meta.

property dtype
field(item)

Return column[item] for recarray compatibility.

filled(fill_value=None)

Return copy of self, with masked values filled.

If input fill_value supplied then that value is used for all masked entries in the table. Otherwise the individual fill_value defined for each table column is used.

Parameters:
fill_valuestr

If supplied, this fill_value is used for all masked entries in the entire table.

Returns:
filled_table~astropy.table.Table

New table with masked values filled

classmethod from_pandas(dataframe, index=False, units=None)

Create a ~astropy.table.Table from a pandas.DataFrame instance.

In addition to converting generic numeric or string columns, this supports conversion of pandas Date and Time delta columns to ~astropy.time.Time and ~astropy.time.TimeDelta columns, respectively.

Parameters:
dataframepandas.DataFrame

A pandas pandas.DataFrame instance

indexbool

Include the index column in the returned table (default=False)

units: dict

A dict mapping column names to a ~astropy.units.Unit. The columns will have the specified unit in the Table.

Returns:
table~astropy.table.Table

A ~astropy.table.Table (or subclass) instance

Raises:
ImportError

If pandas is not installed

Examples

Here we convert a pandas.DataFrame instance to a ~astropy.table.QTable.

>>> import numpy as np
>>> import pandas as pd
>>> from astropy.table import QTable
>>> time = pd.Series(['1998-01-01', '2002-01-01'], dtype='datetime64[ns]')
>>> dt = pd.Series(np.array([1, 300], dtype='timedelta64[s]'))
>>> df = pd.DataFrame({'time': time})
>>> df['dt'] = dt
>>> df['x'] = [3., 4.]
>>> with pd.option_context('display.max_columns', 20):
...     print(df)
        time              dt    x
0 1998-01-01 0 days 00:00:01  3.0
1 2002-01-01 0 days 00:05:00  4.0
>>> QTable.from_pandas(df)
<QTable length=2>
          time              dt       x
          Time          TimeDelta float64
----------------------- --------- -------
1998-01-01T00:00:00.000       1.0     3.0
2002-01-01T00:00:00.000     300.0     4.0
group_by(keys)

Group this table by the specified keys.

This effectively splits the table into groups which correspond to unique values of the keys grouping object. The output is a new ~astropy.table.TableGroups which contains a copy of this table but sorted by row according to keys.

The keys input to group_by can be specified in different ways:

  • String or list of strings corresponding to table column name(s)

  • Numpy array (homogeneous or structured) with same length as this table

  • ~astropy.table.Table with same length as this table

Parameters:
keysstr, list of str, numpy array, or ~astropy.table.Table

Key grouping object

Returns:
out~astropy.table.Table

New table with groups set

property groups
property has_masked_columns

True if table has any MaskedColumn columns.

This does not check for mixin columns that may have masked values, use the has_masked_values property in that case.

property has_masked_values

True if column in the table has values which are masked.

This may be relatively slow for large tables as it requires checking the mask values of each column.

property has_mixin_columns

True if table has any mixin columns (defined as columns that are not Column subclasses).

property iloc

Return a TableILoc object that can be used for retrieving indexed rows in the order they appear in the index.

index_column(name)

Return the positional index of column name.

Parameters:
namestr

column name

Returns:
indexint

Positional index of column name.

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z

Get index of column ‘b’ of the table:

>>> t.index_column('b')
1
index_mode(mode)

Return a context manager for an indexing mode.

Parameters:
modestr

Either ‘freeze’, ‘copy_on_getitem’, or ‘discard_on_copy’. In ‘discard_on_copy’ mode, indices are not copied whenever columns or tables are copied. In ‘freeze’ mode, indices are not modified whenever columns are modified; at the exit of the context, indices refresh themselves based on column values. This mode is intended for scenarios in which one intends to make many additions or modifications in an indexed column. In ‘copy_on_getitem’ mode, indices are copied when taking column slices as well as table slices, so col[i0:i1] will preserve indices.

property indices

Return the indices associated with columns of the table as a TableIndices object.

info
insert_row(index, vals=None, mask=None)

Add a new row before the given index position in the table.

The vals argument can be:

sequence (e.g. tuple or list)

Column values in the same order as table columns.

mapping (e.g. dict)

Keys corresponding to column names. Missing values will be filled with np.zeros for the column dtype.

None

All values filled with np.zeros for the column dtype.

The mask attribute should give (if desired) the mask for the values. The type of the mask should match that of the values, i.e. if vals is an iterable, then mask should also be an iterable with the same length, and if vals is a mapping, then mask should be a dictionary.

Parameters:
valstuple, list, dict or None

Use the specified values in the new row

masktuple, list, dict or None

Use the specified mask values in the new row

items()
itercols()

Iterate over the columns of this table.

Examples

To iterate over the columns of a table:

>>> t = Table([[1], [2]])
>>> for col in t.itercols():
...     print(col)
col0
----
   1
col1
----
   2

Using itercols() is similar to for col in t.columns.values() but is syntactically preferred.

iterrows(*names)

Iterate over rows of table returning a tuple of values for each row.

This method is especially useful when only a subset of columns are needed.

The iterrows method can be substantially faster than using the standard Table row iteration (e.g. for row in tbl:), since that returns a new ~astropy.table.Row object for each row and accessing a column in that row (e.g. row['col0']) is slower than tuple access.

Parameters:
nameslist

List of column names (default to all columns if no names provided)

Returns:
rowsiterable

Iterator returns tuples of row values

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table({'a': [1, 2, 3],
...            'b': [1.0, 2.5, 3.0],
...            'c': ['x', 'y', 'z']})

To iterate row-wise using column names:

>>> for a, c in t.iterrows('a', 'c'):
...     print(a, c)
1 x
2 y
3 z
keep_columns(names)

Keep only the columns specified (remove the others).

Parameters:
namesstr or iterable of str

The columns to keep. All other columns will be removed.

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1, 2, 3],[0.1, 0.2, 0.3],['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z

Keep only column ‘a’ of the table:

>>> t.keep_columns('a')
>>> print(t)
 a
---
  1
  2
  3

Keep columns ‘a’ and ‘c’ of the table:

>>> t = Table([[1, 2, 3],[0.1, 0.2, 0.3],['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> t.keep_columns(['a', 'c'])
>>> print(t)
 a   c
--- ---
  1   x
  2   y
  3   z
keys()
property loc

Return a TableLoc object that can be used for retrieving rows by index in a given data range. Note that both loc and iloc work only with single-column indices.

property loc_indices

Return a TableLocIndices object that can be used for retrieving the row indices corresponding to given table index key value or values.

property mask
property masked
meta = None
more(max_lines=None, max_width=None, show_name=True, show_unit=None, show_dtype=False)

Interactively browse table with a paging interface.

Supported keys:

f, <space> : forward one page
b : back one page
r : refresh same page
n : next row
p : previous row
< : go to beginning
> : go to end
q : quit browsing
h : print this help
Parameters:
max_linesint

Maximum number of lines in table output

max_widthint or None

Maximum character width of output

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is False.

pformat(max_lines=None, max_width=None, show_name=True, show_unit=None, show_dtype=False, html=False, tableid=None, align=None, tableclass=None)
Return a list of lines for the formatted string representation of

the table.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default is taken from the configuration item astropy.conf.max_lines. If a negative value of max_lines is supplied then there is no line limit applied.

The same applies for max_width except the configuration item is astropy.conf.max_width.

Parameters:
max_linesint or None

Maximum number of rows to output

max_widthint or None

Maximum character width of output

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is True.

htmlbool

Format the output as an HTML table. Default is False.

tableidstr or None

An ID tag for the table; only used if html is set. Default is “table{id}”, where id is the unique integer id of the table object, id(self)

alignstr or list or tuple or None

Left/right alignment of columns. Default is right (None) for all columns. Other allowed values are ‘>’, ‘<’, ‘^’, and ‘0=’ for right, left, centered, and 0-padded, respectively. A list of strings can be provided for alignment of tables with multiple columns.

tableclassstr or list of str or None

CSS classes for the table; only used if html is set. Default is None.

Returns:
lineslist

Formatted table as a list of strings.

pformat_all(max_lines=-1, max_width=-1, show_name=True, show_unit=None, show_dtype=False, html=False, tableid=None, align=None, tableclass=None)
Return a list of lines for the formatted string representation of

the entire table.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default is taken from the configuration item astropy.conf.max_lines. If a negative value of max_lines is supplied then there is no line limit applied.

The same applies for max_width except the configuration item is astropy.conf.max_width.

Parameters:
max_linesint or None

Maximum number of rows to output

max_widthint or None

Maximum character width of output

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is True.

htmlbool

Format the output as an HTML table. Default is False.

tableidstr or None

An ID tag for the table; only used if html is set. Default is “table{id}”, where id is the unique integer id of the table object, id(self)

alignstr or list or tuple or None

Left/right alignment of columns. Default is right (None) for all columns. Other allowed values are ‘>’, ‘<’, ‘^’, and ‘0=’ for right, left, centered, and 0-padded, respectively. A list of strings can be provided for alignment of tables with multiple columns.

tableclassstr or list of str or None

CSS classes for the table; only used if html is set. Default is None.

Returns:
lineslist

Formatted table as a list of strings.

pprint(max_lines=None, max_width=None, show_name=True, show_unit=None, show_dtype=False, align=None)

Print a formatted string representation of the table.

If no value of max_lines is supplied then the height of the screen terminal is used to set max_lines. If the terminal height cannot be determined then the default is taken from the configuration item astropy.conf.max_lines. If a negative value of max_lines is supplied then there is no line limit applied.

The same applies for max_width except the configuration item is astropy.conf.max_width.

Parameters:
max_linesint or None

Maximum number of lines in table output.

max_widthint or None

Maximum character width of output.

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is False.

alignstr or list or tuple or None

Left/right alignment of columns. Default is right (None) for all columns. Other allowed values are ‘>’, ‘<’, ‘^’, and ‘0=’ for right, left, centered, and 0-padded, respectively. A list of strings can be provided for alignment of tables with multiple columns.

pprint_all(max_lines=-1, max_width=-1, show_name=True, show_unit=None, show_dtype=False, align=None)

Print a formatted string representation of the entire table.

This method is the same as astropy.table.Table.pprint except that the default max_lines and max_width are both -1 so that by default the entire table is printed instead of restricting to the size of the screen terminal.

Parameters:
max_linesint or None

Maximum number of lines in table output.

max_widthint or None

Maximum character width of output.

show_namebool

Include a header row for column names. Default is True.

show_unitbool

Include a header row for unit. Default is to show a row for units only if one or more columns has a defined value for the unit.

show_dtypebool

Include a header row for column dtypes. Default is False.

alignstr or list or tuple or None

Left/right alignment of columns. Default is right (None) for all columns. Other allowed values are ‘>’, ‘<’, ‘^’, and ‘0=’ for right, left, centered, and 0-padded, respectively. A list of strings can be provided for alignment of tables with multiple columns.

pprint_exclude_names

Maintain tuple that controls table column visibility for print output.

This is a descriptor that inherits from MetaAttribute so that the attribute value is stored in the table meta[‘__attributes__’].

This gets used for the pprint_include_names and pprint_exclude_names Table attributes.

pprint_include_names

Maintain tuple that controls table column visibility for print output.

This is a descriptor that inherits from MetaAttribute so that the attribute value is stored in the table meta[‘__attributes__’].

This gets used for the pprint_include_names and pprint_exclude_names Table attributes.

property read

Read and parse a data table and return as a Table.

This function provides the Table interface to the astropy unified I/O layer. This allows easily reading a file in many supported data formats using syntax such as:

>>> from astropy.table import Table
>>> dat = Table.read('table.dat', format='ascii')
>>> events = Table.read('events.fits', format='fits')

Get help on the available readers for Table using the``help()`` method:

>>> Table.read.help()  # Get help reading Table and list supported formats
>>> Table.read.help('fits')  # Get detailed help on Table FITS reader
>>> Table.read.list_formats()  # Print list of available formats

See also: https://docs.astropy.org/en/stable/io/unified.html

Parameters:
*argstuple, optional

Positional arguments passed through to data reader. If supplied the first argument is typically the input filename.

formatstr

File format specifier.

unitslist, dict, optional

List or dict of units to apply to columns

descriptionslist, dict, optional

List or dict of descriptions to apply to columns

**kwargsdict, optional

Keyword arguments passed through to data reader.

Returns:
out~astropy.table.Table

Table corresponding to file contents

remove_column(name)

Remove a column from the table.

This can also be done with:

del table[name]
Parameters:
namestr

Name of column to remove

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z

Remove column ‘b’ from the table:

>>> t.remove_column('b')
>>> print(t)
 a   c
--- ---
  1   x
  2   y
  3   z

To remove several columns at the same time use remove_columns.

remove_columns(names)

Remove several columns from the table.

Parameters:
namesstr or iterable of str

Names of the columns to remove

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...     names=('a', 'b', 'c'))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z

Remove columns ‘b’ and ‘c’ from the table:

>>> t.remove_columns(['b', 'c'])
>>> print(t)
 a
---
  1
  2
  3

Specifying only a single column also works. Remove column ‘b’ from the table:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...     names=('a', 'b', 'c'))
>>> t.remove_columns('b')
>>> print(t)
 a   c
--- ---
  1   x
  2   y
  3   z

This gives the same as using remove_column.

remove_indices(colname)

Remove all indices involving the given column. If the primary index is removed, the new primary index will be the most recently added remaining index.

Parameters:
colnamestr

Name of column

remove_row(index)

Remove a row from the table.

Parameters:
indexint

Index of row to remove

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z

Remove row 1 from the table:

>>> t.remove_row(1)
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  3 0.3   z

To remove several rows at the same time use remove_rows.

remove_rows(row_specifier)

Remove rows from the table.

Parameters:
row_specifierslice or int or array of int

Specification for rows to remove

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z

Remove rows 0 and 2 from the table:

>>> t.remove_rows([0, 2])
>>> print(t)
 a   b   c
--- --- ---
  2 0.2   y

Note that there are no warnings if the slice operator extends outside the data:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3], ['x', 'y', 'z']],
...           names=('a', 'b', 'c'))
>>> t.remove_rows(slice(10, 20, 1))
>>> print(t)
 a   b   c
--- --- ---
  1 0.1   x
  2 0.2   y
  3 0.3   z
rename_column(name, new_name)

Rename a column.

This can also be done directly by setting the name attribute of the info property of the column:

table[name].info.name = new_name
Parameters:
namestr

The current name of the column.

new_namestr

The new name for the column

Examples

Create a table with three columns ‘a’, ‘b’ and ‘c’:

>>> t = Table([[1,2],[3,4],[5,6]], names=('a','b','c'))
>>> print(t)
 a   b   c
--- --- ---
  1   3   5
  2   4   6

Renaming column ‘a’ to ‘aa’:

>>> t.rename_column('a' , 'aa')
>>> print(t)
 aa  b   c
--- --- ---
  1   3   5
  2   4   6
rename_columns(names, new_names)

Rename multiple columns.

Parameters:
nameslist, tuple

A list or tuple of existing column names.

new_nameslist, tuple

A list or tuple of new column names.

Examples

Create a table with three columns ‘a’, ‘b’, ‘c’:

>>> t = Table([[1,2],[3,4],[5,6]], names=('a','b','c'))
>>> print(t)
  a   b   c
 --- --- ---
  1   3   5
  2   4   6

Renaming columns ‘a’ to ‘aa’ and ‘b’ to ‘bb’:

>>> names = ('a','b')
>>> new_names = ('aa','bb')
>>> t.rename_columns(names, new_names)
>>> print(t)
 aa  bb   c
--- --- ---
  1   3   5
  2   4   6
replace_column(name, col, copy=True)

Replace column name with the new col object.

The behavior of copy for Column objects is: - copy=True: new class instance with a copy of data and deep copy of meta - copy=False: new class instance with same data and a key-only copy of meta

For mixin columns: - copy=True: new class instance with copy of data and deep copy of meta - copy=False: original instance (no copy at all)

Parameters:
namestr

Name of column to replace

col~astropy.table.Column or ~numpy.ndarray or sequence

New column object to replace the existing column.

copybool

Make copy of the input col, default=True

Examples

Replace column ‘a’ with a float version of itself:

>>> t = Table([[1, 2, 3], [0.1, 0.2, 0.3]], names=('a', 'b'))
>>> float_a = t['a'].astype(float)
>>> t.replace_column('a', float_a)
reverse()

Reverse the row order of table rows. The table is reversed in place and there are no function arguments.

Examples

Create a table with three columns:

>>> t = Table([['Max', 'Jo', 'John'], ['Miller','Miller','Jackson'],
...         [12,15,18]], names=('firstname','name','tel'))
>>> print(t)
firstname   name  tel
--------- ------- ---
      Max  Miller  12
       Jo  Miller  15
     John Jackson  18

Reversing order:

>>> t.reverse()
>>> print(t)
firstname   name  tel
--------- ------- ---
     John Jackson  18
       Jo  Miller  15
      Max  Miller  12
round(decimals=0)

Round numeric columns in-place to the specified number of decimals. Non-numeric columns will be ignored.

Parameters:
decimals: int, dict

Number of decimals to round the columns to. If a dict is given, the columns will be rounded to the number specified as the value. If a certain column is not in the dict given, it will remain the same.

Examples

Create three columns with different types:

>>> t = Table([[1, 4, 5], [-25.55, 12.123, 85],
...     ['a', 'b', 'c']], names=('a', 'b', 'c'))
>>> print(t)
 a    b     c
--- ------ ---
  1 -25.55   a
  4 12.123   b
  5   85.0   c

Round them all to 0:

>>> t.round(0)
>>> print(t)
 a    b    c
--- ----- ---
  1 -26.0   a
  4  12.0   b
  5  85.0   c

Round column ‘a’ to -1 decimal:

>>> t.round({'a':-1})
>>> print(t)
 a    b    c
--- ----- ---
  0 -26.0   a
  0  12.0   b
  0  85.0   c
setdefault(name, default)

Ensure a column named name exists.

If name is already present then default is ignored. Otherwise default can be any data object which is acceptable as a ~astropy.table.Table column object or can be converted. This includes mixin columns and scalar or length=1 objects which get broadcast to match the table length.

Parameters:
namestr

Name of the column.

defaultobject

Data object for the new column.

Returns:
~astropy.table.Column, ~astropy.table.MaskedColumn or mixin-column type

The column named name if it is present already, or the validated default converted to a column otherwise.

Raises:
TypeError

If the table is empty and default is a scalar object.

Examples

Start with a simple table:

>>> t0 = Table({"a": ["Ham", "Spam"]})
>>> t0
<Table length=2>
 a
str4
----
 Ham
Spam

Trying to add a column that already exists does not modify it:

>>> t0.setdefault("a", ["Breakfast"])
<Column name='a' dtype='str4' length=2>
 Ham
Spam
>>> t0
<Table length=2>
 a
str4
----
 Ham
Spam

But if the column does not exist it will be created with the default value:

>>> t0.setdefault("approved", False)
<Column name='approved' dtype='bool' length=2>
False
False
>>> t0
<Table length=2>
 a   approved
str4   bool
---- --------
 Ham    False
Spam    False
show_in_browser(max_lines=5000, jsviewer=False, browser='default', jskwargs={'use_local_files': True}, tableid=None, table_class='display compact', css=None, show_row_index='idx')

Deprecated since version 6.1: We are planning on deprecating show_in_browser in the future. If you are actively using this method, please let us know at https://github.com/astropy/astropy/issues/16067

Render the table in HTML and show it in a web browser.

Parameters:
max_linesint

Maximum number of rows to export to the table (set low by default to avoid memory issues, since the browser view requires duplicating the table in memory). A negative value of max_lines indicates no row limit.

jsviewerbool

If True, prepends some javascript headers so that the table is rendered as a DataTables data table. This allows in-browser searching & sorting.

browserstr

Any legal browser name, e.g. 'firefox', 'chrome', 'safari' (for mac, you may need to use 'open -a "/Applications/Google Chrome.app" {}' for Chrome). If 'default', will use the system default browser.

jskwargsdict

Passed to the astropy.table.JSViewer init. Defaults to {'use_local_files': True} which means that the JavaScript libraries will be served from local copies.

tableidstr or None

An html ID tag for the table. Default is table{id}, where id is the unique integer id of the table object, id(self).

table_classstr or None

A string with a list of HTML classes used to style the table. Default is “display compact”, and other possible values can be found in https://www.datatables.net/manual/styling/classes

cssstr

A valid CSS string declaring the formatting for the table. Defaults to astropy.table.jsviewer.DEFAULT_CSS.

show_row_indexstr or False

If this does not evaluate to False, a column with the given name will be added to the version of the table that gets displayed. This new column shows the index of the row in the table itself, even when the displayed table is re-sorted by another column. Note that if a column with this name already exists, this option will be ignored. Defaults to “idx”.

show_in_notebook(tableid=None, css=None, display_length=50, table_class='astropy-default', show_row_index='idx')

Deprecated since version 6.1: show_in_notebook() is deprecated as of 6.1 and to create interactive tables it is recommended to use dedicated tools like: - https://github.com/bloomberg/ipydatagrid - https://docs.bokeh.org/en/latest/docs/user_guide/interaction/widgets.html#datatable - https://dash.plotly.com/datatable

Render the table in HTML and show it in the IPython notebook.

Parameters:
tableidstr or None

An html ID tag for the table. Default is table{id}-XXX, where id is the unique integer id of the table object, id(self), and XXX is a random number to avoid conflicts when printing the same table multiple times.

table_classstr or None

A string with a list of HTML classes used to style the table. The special default string (‘astropy-default’) means that the string will be retrieved from the configuration item astropy.table.default_notebook_table_class. Note that these table classes may make use of bootstrap, as this is loaded with the notebook. See this page for the list of classes.

cssstr

A valid CSS string declaring the formatting for the table. Defaults to astropy.table.jsviewer.DEFAULT_CSS_NB.

display_lengthint, optional

Number or rows to show. Defaults to 50.

show_row_indexstr or False

If this does not evaluate to False, a column with the given name will be added to the version of the table that gets displayed. This new column shows the index of the row in the table itself, even when the displayed table is re-sorted by another column. Note that if a column with this name already exists, this option will be ignored. Defaults to “idx”.

Notes

Currently, unlike show_in_browser (with jsviewer=True), this method needs to access online javascript code repositories. This is due to modern browsers’ limitations on accessing local files. Hence, if you call this method while offline (and don’t have a cached version of jquery and jquery.dataTables), you will not get the jsviewer features.

sort(keys=None, *, kind=None, reverse=False)

Sort the table according to one or more keys. This operates on the existing table and does not return a new table.

Parameters:
keysstr or list of str

The key(s) to order the table by. If None, use the primary index of the Table.

kind{‘quicksort’, ‘mergesort’, ‘heapsort’, ‘stable’}, optional

Sorting algorithm used by numpy.argsort.

reversebool

Sort in reverse order (default=False)

Examples

Create a table with 3 columns:

>>> t = Table([['Max', 'Jo', 'John'], ['Miller', 'Miller', 'Jackson'],
...            [12, 15, 18]], names=('firstname', 'name', 'tel'))
>>> print(t)
firstname   name  tel
--------- ------- ---
      Max  Miller  12
       Jo  Miller  15
     John Jackson  18

Sorting according to standard sorting rules, first ‘name’ then ‘firstname’:

>>> t.sort(['name', 'firstname'])
>>> print(t)
firstname   name  tel
--------- ------- ---
     John Jackson  18
       Jo  Miller  15
      Max  Miller  12

Sorting according to standard sorting rules, first ‘firstname’ then ‘tel’, in reverse order:

>>> t.sort(['firstname', 'tel'], reverse=True)
>>> print(t)
firstname   name  tel
--------- ------- ---
      Max  Miller  12
     John Jackson  18
       Jo  Miller  15
to_pandas(index=None, use_nullable_int=True)

Return a pandas.DataFrame instance.

The index of the created DataFrame is controlled by the index argument. For index=True or the default None, an index will be specified for the DataFrame if there is a primary key index on the Table and if it corresponds to a single column. If index=False then no DataFrame index will be specified. If index is the name of a column in the table then that will be the DataFrame index.

In addition to vanilla columns or masked columns, this supports Table mixin columns like Quantity, Time, or SkyCoord. In many cases these objects have no analog in pandas and will be converted to a “encoded” representation using only Column or MaskedColumn. The exception is Time or TimeDelta columns, which will be converted to the corresponding representation in pandas using np.datetime64 or np.timedelta64. See the example below.

Parameters:
indexNone, bool, str

Specify DataFrame index mode

use_nullable_intbool, default=True

Convert integer MaskedColumn to pandas nullable integer type. If use_nullable_int=False or the pandas version does not support nullable integer types (version < 0.24), then the column is converted to float with NaN for missing elements and a warning is issued.

Returns:
dataframepandas.DataFrame

A pandas pandas.DataFrame instance

Raises:
ImportError

If pandas is not installed

ValueError

If the Table has multi-dimensional columns

Examples

Here we convert a table with a few mixins to a pandas.DataFrame instance.

>>> import pandas as pd
>>> from astropy.table import QTable
>>> import astropy.units as u
>>> from astropy.time import Time, TimeDelta
>>> from astropy.coordinates import SkyCoord
>>> q = [1, 2] * u.m
>>> tm = Time([1998, 2002], format='jyear')
>>> sc = SkyCoord([5, 6], [7, 8], unit='deg')
>>> dt = TimeDelta([3, 200] * u.s)
>>> t = QTable([q, tm, sc, dt], names=['q', 'tm', 'sc', 'dt'])
>>> df = t.to_pandas(index='tm')
>>> with pd.option_context('display.max_columns', 20):
...     print(df)
              q  sc.ra  sc.dec              dt
tm
1998-01-01  1.0    5.0     7.0 0 days 00:00:03
2002-01-01  2.0    6.0     8.0 0 days 00:03:20
update(other, copy=True)

Perform a dictionary-style update and merge metadata.

The argument other must be a |Table|, or something that can be used to initialize a table. Columns from (possibly converted) other are added to this table. In case of matching column names the column from this table is replaced with the one from other. If other is a |Table| instance then |= is available as alternate syntax for in-place update and | can be used merge data to a new table.

Parameters:
othertable-like

Data to update this table with.

copybool

Whether the updated columns should be copies of or references to the originals.

Examples

Update a table with another table:

>>> t1 = Table({'a': ['foo', 'bar'], 'b': [0., 0.]}, meta={'i': 0})
>>> t2 = Table({'b': [1., 2.], 'c': [7., 11.]}, meta={'n': 2})
>>> t1.update(t2)
>>> t1
<Table length=2>
 a      b       c
str3 float64 float64
---- ------- -------
 foo     1.0     7.0
 bar     2.0    11.0
>>> t1.meta
{'i': 0, 'n': 2}

Update a table with a dictionary:

>>> t = Table({'a': ['foo', 'bar'], 'b': [0., 0.]})
>>> t.update({'b': [1., 2.]})
>>> t
<Table length=2>
 a      b
str3 float64
---- -------
 foo     1.0
 bar     2.0
values()
values_equal(other)

Element-wise comparison of table with another table, list, or scalar.

Returns a Table with the same columns containing boolean values showing result of comparison.

Parameters:
othertable-like object or list or scalar

Object to compare with table

Examples

Compare one Table with other:

>>> t1 = Table([[1, 2], [4, 5], [-7, 8]], names=('a', 'b', 'c'))
>>> t2 = Table([[1, 2], [-4, 5], [7, 8]], names=('a', 'b', 'c'))
>>> t1.values_equal(t2)
<Table length=2>
 a     b     c
bool  bool  bool
---- ----- -----
True False False
True  True  True
property write

Write this Table object out in the specified format.

This function provides the Table interface to the astropy unified I/O layer. This allows easily writing a file in many supported data formats using syntax such as:

>>> from astropy.table import Table
>>> dat = Table([[1, 2], [3, 4]], names=('a', 'b'))
>>> dat.write('table.dat', format='ascii')

Get help on the available writers for Table using the``help()`` method:

>>> Table.write.help()  # Get help writing Table and list supported formats
>>> Table.write.help('fits')  # Get detailed help on Table FITS writer
>>> Table.write.list_formats()  # Print list of available formats

The serialize_method argument is explained in the section on Table serialization methods.

See also: https://docs.astropy.org/en/stable/io/unified.html

Parameters:
*argstuple, optional

Positional arguments passed through to data writer. If supplied the first argument is the output filename.

formatstr

File format specifier.

serialize_methodstr, dict, optional

Serialization method specifier for columns.

**kwargsdict, optional

Keyword arguments passed through to data writer.