CalcE2¶
- class lsst.analysis.tools.actions.vector.CalcE2(*args, **kw)¶
Bases:
VectorAction
Calculate \(e_2\) (distortion-type) or \(g_2\) (shear-type).
The definitions are as follows:
\[\begin{split}e_2 &= 2I_{xy}/(I_{xx}+I_{yy}) \\ g_2 &= 2I_{xy}/(I_{xx}+I_{yy}+2\sqrt{(I_{xx}I_{yy}-I_{xy}^{2})}).\end{split}\]Notes
This is a shape measurement used for doing QA on the ellipticity of the sources.
Attributes Summary
The column name to get the xx shape component from.
The column name to get the xy shape component from.
The column name to get the yy shape component from.
The type of ellipticity to calculate (
str
, default'distortion'
)Methods Summary
__call__
(data, **kwargs)Call self as a function.
Return the schema an
AnalysisAction
expects to be present in the arguments supplied to the __call__ method.Attributes Documentation
- ellipticityType¶
The type of ellipticity to calculate (
str
, default'distortion'
)Allowed values:
'distortion'
Distortion, defined as \(2I_{xy}/(I_{xx}+I_{yy})\)
'shear'
Shear, defined as \(2I_{xy}/(I_{xx}+I_{yy}+2\sqrt{I_{xx}I_{yy}-I_{xy}^2})\)
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:
- result
KeyedDataSchema
The schema this action requires to be present when calling this action, keys are unformatted.
- result