BaseTractBuilder

class lsst.skymap.BaseTractBuilder(config)

Bases: object

Base class for algorithms that define patches within the tract.

Parameters:
config : lsst.pexConfig.Config

Input for configuring the algorithm

Methods Summary

getPackedConfig(config) Get a packed config suitable for using in a sha1.
getPatchBorder()
getPatchIndexPair(sequentialIndex) Convert sequential index into patch index (x,y) pair.
getPatchInfo(index, tractWcs) Return information for the specified patch.
getPatchInnerDimensions() Get dimensions of inner region of the patches (all are the same)
getSequentialPatchIndex(patchInfo) Return a single integer that uniquely identifies the given patch within this tract.
getSequentialPatchIndexFromPair(index) Return a single integer that uniquely identifies the patch index within the tract.
setupPatches(minBBox, wcs) Set up the patches of a particular size in a tract.

Methods Documentation

getPackedConfig(config)

Get a packed config suitable for using in a sha1.

Parameters:
config : lsst.skymap.BaseTractBuilderConfig
Returns:
configPacked : bytes
getPatchBorder()
getPatchIndexPair(sequentialIndex)

Convert sequential index into patch index (x,y) pair.

Parameters:
sequentialIndex : int
Returns:
x, y : lsst.skymap.Index2D
getPatchInfo(index, tractWcs)

Return information for the specified patch.

Parameters:
index : lsst.skymap.Index2D or Iterable [int, int]

Index of patch, as Index2D or pair of ints; or a sequential index as returned by getSequentialPatchIndex; negative values are not supported.

tractWcs : lsst.afw.geom.SkyWcs

WCS associated with the tract.
Returns:
result : lsst.skymap.PatchInfo

The patch info for that index.
Raises:
IndexError

If index is out of range.
getPatchInnerDimensions()

Get dimensions of inner region of the patches (all are the same)

getSequentialPatchIndex(patchInfo)

Return a single integer that uniquely identifies the given patch within this tract.

Parameters:
patchInfo : lsst.skymap.PatchInfo
Returns:
sequentialIndex : int
getSequentialPatchIndexFromPair(index)

Return a single integer that uniquely identifies the patch index within the tract.

Parameters:
index : lsst.skymap.Index2D or Iterable [int, int]
Returns:
sequentialIndex : int
setupPatches(minBBox, wcs)

Set up the patches of a particular size in a tract.

We grow the tract bounding box to hold an exact multiple of the desired size (patchInnerDimensions or numCellsPerPatchInner*cellInnerDimensions), while keeping the center roughly the same. We return the final tract bounding box, and the number of patches in each dimension (as an Index2D).

Parameters:
minBBox : lsst.geom.Box2I

Minimum bounding box for tract

wcs : lsst.afw.geom.SkyWcs

Wcs object
Returns:
bbox : `lsst.geom.Box2I

final bounding box, number of patches

numPatches : lsst.skymap.Index2D