lsst.ip.diffim  16.0-14-g8a3b804+2
Classes | Functions
lsst.ip.diffim.dcrModel Namespace Reference

Classes

class  DcrModel
 

Functions

def applyDcr (maskedImage, dcr, warpCtrl, bbox=None, useInverse=False)
 
def calculateDcr (visitInfo, wcs, filterInfo, dcrNumSubfilters)
 
def calculateImageParallacticAngle (visitInfo, wcs)
 
def wavelengthGenerator (filterInfo, dcrNumSubfilters)
 

Function Documentation

◆ applyDcr()

def lsst.ip.diffim.dcrModel.applyDcr (   maskedImage,
  dcr,
  warpCtrl,
  bbox = None,
  useInverse = False 
)
Shift a masked image.

Parameters
----------
maskedImage : `lsst.afw.image.MaskedImage`
    The input masked image to shift.
dcr : `lsst.afw.geom.Extent2I`
    Shift calculated with ``calculateDcr``.
warpCtrl : `lsst.afw.math.WarpingControl`
    Configuration settings for warping an image
bbox : `lsst.afw.geom.Box2I`, optional
    Sub-region of the masked image to shift.
    Shifts the entire image if None (Default).
useInverse : `bool`, optional
    Use the reverse of ``dcr`` for the shift. Default: False

Returns
-------
`lsst.afw.image.maskedImageF`
    A masked image, with the pixels within the bounding box shifted.

Definition at line 536 of file dcrModel.py.

◆ calculateDcr()

def lsst.ip.diffim.dcrModel.calculateDcr (   visitInfo,
  wcs,
  filterInfo,
  dcrNumSubfilters 
)
Calculate the shift in pixels of an exposure due to DCR.

Parameters
----------
visitInfo : `lsst.afw.image.VisitInfo`
    Metadata for the exposure.
wcs : `lsst.afw.geom.SkyWcs`
    Coordinate system definition (wcs) for the exposure.
filterInfo : `lsst.afw.image.Filter`
    The filter definition, set in the current instruments' obs package.
dcrNumSubfilters : `int`
    Number of sub-filters used to model chromatic effects within a band.

Returns
-------
`lsst.afw.geom.Extent2I`
    The 2D shift due to DCR, in pixels.

Definition at line 568 of file dcrModel.py.

◆ calculateImageParallacticAngle()

def lsst.ip.diffim.dcrModel.calculateImageParallacticAngle (   visitInfo,
  wcs 
)
Calculate the total sky rotation angle of an exposure.

Parameters
----------
visitInfo : `lsst.afw.image.VisitInfo`
    Metadata for the exposure.
wcs : `lsst.afw.geom.SkyWcs`
    Coordinate system definition (wcs) for the exposure.

Returns
-------
`lsst.geom.Angle`
    The rotation of the image axis, East from North.
    Equal to the parallactic angle plus any additional rotation of the
    coordinate system.
    A rotation angle of 0 degrees is defined with
    North along the +y axis and East along the +x axis.
    A rotation angle of 90 degrees is defined with
    North along the +x axis and East along the -y axis.

Definition at line 608 of file dcrModel.py.

◆ wavelengthGenerator()

def lsst.ip.diffim.dcrModel.wavelengthGenerator (   filterInfo,
  dcrNumSubfilters 
)
Iterate over the wavelength endpoints of subfilters.

Parameters
----------
filterInfo : `lsst.afw.image.Filter`
    The filter definition, set in the current instruments' obs package.
dcrNumSubfilters : `int`
    Number of sub-filters used to model chromatic effects within a band.

Yields
------
`tuple` of two `float`
    The next set of wavelength endpoints for a subfilter, in nm.

Definition at line 639 of file dcrModel.py.