Catalog

class mpdaf.sdetect.Catalog(*args, **kwargs)

Bases: astropy.table.Table

This class inherits from astropy.table.Table. Its goal is to manage a list of objects.

Methods Summary

edgedist(wcs[, ra, dec])	Return the smallest distance of all catalog sources center to the edge of the WCS of the given image.
from_path(path[, fmt, pattern])	Construct a catalog from a list of source objects which are contains in the directory given as input.
from_sources(sources[, fmt])	Construct a catalog from a list of source objects.
masked_invalid()	Mask where invalid values occur (NaNs or infs or -9999 or ‘’).
match(cat2[, radius, colc1, colc2, full_output])	Match elements of the current catalog with an other (in RA, DEC).
plot_id(ax, wcs[, iden, ra, dec, symb, ...])	This function displays the id of the catalog.
plot_symb(ax, wcs[, ra, dec, symb, col, alpha])	This function plots the sources location from the catalog.
read(*args, **kwargs)
select(wcs[, ra, dec, margin])	Select all sources from catalog which are inside the given WCS and return a new catalog.

Methods Documentation

edgedist(wcs, ra='RA', dec='DEC')

Return the smallest distance of all catalog sources center to the edge of the WCS of the given image.

Parameters:

wcs : WCS

Image WCS

ra : str

Name of the column that contains RA values in degrees

dec : str

Name of the column that contains DEC values in degrees

Returns:

out : numpy.array in arcsec units

classmethod from_path(path, fmt='default', pattern='*.fits')

Construct a catalog from a list of source objects which are contains in the directory given as input.

The new catalog will contain all data stored in the primary headers and in the tables extensions of the sources:

• a column per header fits (‘SIMPLE’, ‘BITPIX’, ‘NAXIS’, ‘EXTEND’, ‘DATE’, ‘AUTHOR’, ‘COM*’ and ‘HIST*’ are excluded)
• two columns per magnitude band: [BAND] [BAND]_ERR
• three columns per redshift Z_[Z_DESC], Z_[Z_DESC]_MIN and Z_[Z_DESC]_MAX
• several columns per line.

The lines columns depend of the format. By default the columns names are created around unique LINE name [LINE]_[LINES columns names]. But it is possible to use a working format. [LINES columns names]_xxx where xxx is the number of lines present in each source.

Parameters:

path : str

Directory containing Source files

fmt : str ‘working’|’default’

Format of the catalog. The format differs for the LINES table.

pattern : str

Pattern used to select the files, default to *.fits.

classmethod from_sources(sources, fmt='default')

Construct a catalog from a list of source objects.

The new catalog will contain all data stored in the primary headers and in the tables extensions of the sources:

• a column per header fits (‘SIMPLE’, ‘BITPIX’, ‘NAXIS’, ‘EXTEND’, ‘DATE’, ‘AUTHOR’, ‘COM*’ and ‘HIST*’ are excluded)
• two columns per magnitude band: [BAND] [BAND]_ERR
• three columns per redshift Z_[Z_DESC], Z_[Z_DESC]_MIN and Z_[Z_DESC]_MAX
• several columns per line.

The lines columns depend of the format. By default the columns names are created around unique LINE name [LINE]_[LINES columns names]. But it is possible to use a working format. [LINES columns names]_xxx where xxx is the number of lines present in each source.

Parameters:

sources : list< mpdaf.sdetect.Source >

List of mpdaf.sdetect.Source objects

fmt : str ‘working’|’default’

Format of the catalog. The format differs for the LINES table.

masked_invalid()

Mask where invalid values occur (NaNs or infs or -9999 or ‘’).

match(cat2, radius=1, colc1=('RA', 'DEC'), colc2=('RA', 'DEC'), full_output=True)

Match elements of the current catalog with an other (in RA, DEC).

Parameters:

cat2 : astropy.table.Table

Catalog to match.

radius : float

Matching size in arcsec (default 1).

colc1: tuple

(‘RA’,’DEC’) name of ra,dec columns of input table

colc2: tuple

(‘RA’,’DEC’) name of ra,dec columns of cat2

Returns:

if full_output is True

out : astropy.Table, astropy.Table, astropy.Table

match, nomatch1, nomatch2

else

out : astropy.Table

match

match: table of matched elements in RA,DEC

nomatch1: sub-table of non matched elements of the current catalog

nomatch2: sub-table of non matched elements of the catalog cat2

plot_id(ax, wcs, iden='ID', ra='RA', dec='DEC', symb=0.2, alpha=0.5, col='k', **kwargs)

This function displays the id of the catalog.

Parameters:

ax : matplotlib.axes._subplots.AxesSubplot

Matplotlib axis instance (eg ax = fig.add_subplot(2,3,1)).

wcs : mpdaf.obj.WCS

Image WCS

iden : str

Name of the column that contains ID values

ra : str

Name of the column that contains RA values

dec : str

Name of the column that contains DEC values

symb : float

Size of the circle in arcsec

col : str

Symbol color.

alpha : float

Symbol transparency

kwargs : matplotlib.artist.Artist

kwargs can be used to set additional plotting properties.

plot_symb(ax, wcs, ra='RA', dec='DEC', symb=0.4, col='k', alpha=1.0, **kwargs)

This function plots the sources location from the catalog.

Parameters:

ax : matplotlib.axes._subplots.AxesSubplot

Matplotlib axis instance (eg ax = fig.add_subplot(2,3,1)).

wcs : mpdaf.obj.WCS

Image WCS

ra : str

Name of the column that contains RA values (in degrees)

dec : str

Name of the column that contains DEC values (in degrees)

symb : list or str or float

• List of 3 columns names containing FWHM1,

  FWHM2 and ANGLE values to define the ellipse of each source.

• Column name containing value that will be used

  to define the circle size of each source.

• float in the case of circle with constant size in arcsec

col : str

Symbol color.

alpha : float

Symbol transparency

kwargs : matplotlib.artist.Artist

kwargs can be used to set additional plotting properties.

classmethod read(*args, **kwargs)

select(wcs, ra='RA', dec='DEC', margin=0)

Select all sources from catalog which are inside the given WCS and return a new catalog.

Parameters:

wcs : WCS

Image WCS

ra : str

Name of the column that contains RA values in degrees.

dec : str

Name of the column that contains DEC values in degrees.

margin : int

Margin from the edges.

Returns:

out : mpdaf.sdetect.Catalog