LocalWcs

class lsst.pipe.tasks.functors.LocalWcs(colCD_1_1, colCD_1_2, colCD_2_1, colCD_2_2, **kwargs)

Bases: lsst.pipe.tasks.functors.Functor

Computations using the stored localWcs.

Attributes Summary

columns Columns required to perform calculation
name
noDup
shortname Short name of functor (suitable for column name/dict key)

Methods Summary

__call__(data[, dropna]) Call self as a function.
computeDeltaRaDec(x, y, cd11, cd12, cd21, cd22) Compute the distance on the sphere from x2, y1 to x1, y1.
computeSkySeperation(ra1, dec1, ra2, dec2) Compute the local pixel scale conversion.
difference(data1, data2, **kwargs) Computes difference between functor called on two different ParquetTable objects
fail(df)
getSkySeperationFromPixel(x1, y1, x2, y2, …) Compute the distance on the sphere from x2, y1 to x1, y1.
multilevelColumns(data[, columnIndex, …]) Returns columns needed by functor from multilevel dataset

Attributes Documentation

columns

Columns required to perform calculation

name = 'LocalWcsOperations'
noDup
shortname

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

Methods Documentation

__call__(data, dropna=False)

Call self as a function.

computeDeltaRaDec(x, y, cd11, cd12, cd21, cd22)

Compute the distance on the sphere from x2, y1 to x1, y1.

Parameters:
x : pandas.Series

X pixel coordinate.

y : pandas.Series

Y pixel coordinate.

cd11 : pandas.Series

[1, 1] element of the local Wcs affine transform.

cd11 : pandas.Series

[1, 1] element of the local Wcs affine transform.

cd12 : pandas.Series

[1, 2] element of the local Wcs affine transform.

cd21 : pandas.Series

[2, 1] element of the local Wcs affine transform.

cd22 : pandas.Series

[2, 2] element of the local Wcs affine transform.

Returns:
raDecTuple : tuple

RA and dec conversion of x and y given the local Wcs. Returned units are in radians.

computeSkySeperation(ra1, dec1, ra2, dec2)

Compute the local pixel scale conversion.

Parameters:
ra1 : pandas.Series

Ra of the first coordinate in radians.

dec1 : pandas.Series

Dec of the first coordinate in radians.

ra2 : pandas.Series

Ra of the second coordinate in radians.

dec2 : pandas.Series

Dec of the second coordinate in radians.

Returns:
dist : pandas.Series

Distance on the sphere in radians.

difference(data1, data2, **kwargs)

Computes difference between functor called on two different ParquetTable objects

fail(df)
getSkySeperationFromPixel(x1, y1, x2, y2, cd11, cd12, cd21, cd22)

Compute the distance on the sphere from x2, y1 to x1, y1.

Parameters:
x1 : pandas.Series

X pixel coordinate.

y1 : pandas.Series

Y pixel coordinate.

x2 : pandas.Series

X pixel coordinate.

y2 : pandas.Series

Y pixel coordinate.

cd11 : pandas.Series

[1, 1] element of the local Wcs affine transform.

cd11 : pandas.Series

[1, 1] element of the local Wcs affine transform.

cd12 : pandas.Series

[1, 2] element of the local Wcs affine transform.

cd21 : pandas.Series

[2, 1] element of the local Wcs affine transform.

cd22 : pandas.Series

[2, 2] element of the local Wcs affine transform.

Returns:
Distance : pandas.Series

Arcseconds per pixel at the location of the local WC

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

Returns columns needed by functor from multilevel dataset

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

Parameters:
data : MultilevelParquetTable or DeferredDatasetHandle
columnIndex (optional): 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.