HsmFwhm

class lsst.pipe.tasks.functors.HsmFwhm(filt=None, dataset=None, noDup=None)

Bases: Functor

Functor to calculate the PSF FWHM with second moments measured from the HsmShapeAlgorithm plugin.

This is in units of arcseconds, and assumes the hsc_rings_v1 skymap pixel scale of 0.168 arcseconds/pixel.

Notes

This conversion assumes the PSF is Gaussian, which is not always the case.

Attributes Summary

SIGMA2FWHM
columns	Columns required to perform calculation.
name
noDup	Do not explode by band if used on object table.
pixelScale
shortname	Short name of functor (suitable for column name/dict key).

Methods Summary

__call__(data[, dropna])	Call self as a function.
difference(data1, data2, **kwargs)	Computes difference between functor called on two different DataFrame/Handle objects.
fail(df)
multilevelColumns(data[, columnIndex, ...])	Returns columns needed by functor from multilevel dataset.

Attributes Documentation

SIGMA2FWHM = 2.3548200450309493

columns

Columns required to perform calculation.

name = 'HSM Psf FWHM'

noDup

Do not explode by band if used on object table.

pixelScale = 0.168

shortname

Short name of functor (suitable for column name/dict key).

Methods Documentation

__call__(data, dropna=False)

Call self as a function.

difference(data1, data2, **kwargs)

Computes difference between functor called on two different DataFrame/Handle objects.

fail(df)

multilevelColumns(data, columnIndex=None, returnTuple=False)

Returns columns needed by functor from multilevel dataset.

To access tables with multilevel column structure, the DeferredDatasetHandle or InMemoryDatasetHandle needs to be passed either a list of tuples or a dictionary.

Parameters:

datavarious

The data as either DeferredDatasetHandle, or InMemoryDatasetHandle.

columnIndex (optional): pandas `~pandas.Index` object

Either passed or read in from DeferredDatasetHandle.

`returnTuple`bool

If true, then return a list of tuples rather than the column dictionary specification. This is set to True by CompositeFunctor in order to be able to combine columns from the various component functors.