CalcE1¶

class lsst.analysis.tools.actions.vector.CalcE1(*args, **kw)¶

Bases: VectorAction

Calculate \(e_1\) (distortion-type) or \(g_1\) (shear-type).

The definitions are as follows:

\[\begin{split}e_1&=(I_{xx}-I_{yy})/(I_{xx}+I_{yy}) \\ g_1&=(I_{xx}-I_{yy})/(I_{xx}+I_{yy}+2\sqrt{I_{xx}I_{yy}-I_{xy}^{2}}).\end{split}\]

See also

CalcE
CalcE2

Notes

This is a shape measurement used for doing QA on the ellipticity of the sources.

Attributes Summary

`colXx`	The column name to get the xx shape component from.
`colXy`	The column name to get the xy shape component from.
`colYy`	The column name to get the yy shape component from.
`ellipticityType`	The type of ellipticity to calculate (`str`, default `'distortion'`)

Methods Summary

`__call__`(data, **kwargs)	Call self as a function.
`getInputSchema`()	Return the schema an `AnalysisAction` expects to be present in the arguments supplied to the __call__ method.
`validate`()	Validate the Config, raising an exception if invalid.

Attributes Documentation

colXx¶: The column name to get the xx shape component from. (str, default '{band}_ixx')

colXy¶: The column name to get the xy shape component from. (str, default '{band}_ixy')

colYy¶: The column name to get the yy shape component from. (str, default '{band}_iyy')

ellipticityType¶

The type of ellipticity to calculate (str, default 'distortion')

Allowed values:

'distortion': Distortion, measured as \((I_{xx}-I_{yy})/(I_{xx}+I_{yy})\)
'shear': Shear, measured as \((I_{xx}-I_{yy})/(I_{xx}+I_{yy}+2\sqrt{I_{xx}I_{yy}-I_{xy}^2})\)

Methods Documentation

__call__(data: MutableMapping[str, ndarray[Any, dtype[ScalarType]] | Scalar | HealSparseMap | Tensor], **kwargs) → ndarray[Any, dtype[ScalarType]]¶: Call self as a function.

getInputSchema() → Tensor]]]¶

Return the schema an AnalysisAction expects to be present in the arguments supplied to the __call__ method.

Returns:

resultKeyedDataSchema: The schema this action requires to be present when calling this action, keys are unformatted.

validate()¶

Validate the Config, raising an exception if invalid.

Raises:

lsst.pex.config.FieldValidationError: Raised if verification fails.

Notes

The base class implementation performs type checks on all fields by calling their validate methods.

Complex single-field validation can be defined by deriving new Field types. For convenience, some derived lsst.pex.config.Field-types (ConfigField and ConfigChoiceField) are defined in lsst.pex.config that handle recursing into subconfigs.

Inter-field relationships should only be checked in derived Config classes after calling this method, and base validation is complete.

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CalcE1¶