FitSipDistortionTask¶
- class lsst.meas.astrom.FitSipDistortionTask(**kwargs)¶
Bases:
Task
Fit a TAN-SIP WCS given a list of reference object/source matches.
Methods Summary
display
(revFitter[, exposure, bbox, frame, ...])Display positions and outlier status overlaid on an image.
Empty (clear) the metadata for this Task and all sub-Tasks.
fitWcs
(matches, initWcs[, bbox, refCat, ...])Fit a TAN-SIP WCS from a list of reference object/source matches.
Get metadata for all tasks.
Get the task name as a hierarchical name including parent task names.
getName
()Get the name of the task.
Get a dictionary of all tasks as a shallow copy.
makeField
(doc)Make a
lsst.pex.config.ConfigurableField
for this task.makeInitialWcs
(matches, wcs)Generate a guess Wcs from the astrometric matches
makeSubtask
(name, **keyArgs)Create a subtask as a new instance as the
name
attribute of this task.timer
(name[, logLevel])Context manager to log performance data for an arbitrary block of code.
Methods Documentation
- display(revFitter, exposure=None, bbox=None, frame=0, pause=True)¶
Display positions and outlier status overlaid on an image.
This method is called by fitWcs when display debugging is enabled. It always drops into pdb before returning to allow interactive inspection, and hence it should never be called in non-interactive contexts.
- Parameters:
- revFitter
lsst::meas::astrom::ScaledPolynomialTransformFitter
Fitter object initialized with
fromMatches
for fitting a “reverse” distortion: the mapping from intermediate world coordinates to pixels.- exposure
lsst::afw::image::Exposure
An Exposure or other displayable image on which matches can be overplotted.
- bbox
lsst::afw::geom::Box2I
Bounding box of the region on which matches should be plotted.
- revFitter
- fitWcs(matches, initWcs, bbox=None, refCat=None, sourceCat=None, exposure=None)¶
Fit a TAN-SIP WCS from a list of reference object/source matches.
- Parameters:
- matches
list
oflsst.afw.table.ReferenceMatch
A sequence of reference object/source matches. The following fields are read: - match.first (reference object) coord - match.second (source) centroid
The following fields are written: - match.first (reference object) centroid - match.second (source) centroid - match.distance (on sky separation, in radians)
- initWcs
lsst.afw.geom.SkyWcs
An initial WCS whose CD matrix is used as the final CD matrix.
- bbox
lsst.geom.Box2I
The region over which the WCS will be valid (PARENT pixel coordinates); if
None
or an empty box then computed from matches- refCat
lsst.afw.table.SimpleCatalog
Reference object catalog, or
None
. If provided then all centroids are updated with the new WCS, otherwise only the centroids for ref objects in matches are updated. Required fields are “centroid_x”, “centroid_y”, “coord_ra”, and “coord_dec”.- sourceCat
lsst.afw.table.SourceCatalog
Source catalog, or
None
. If provided then coords are updated with the new WCS; otherwise only the coords for sources in matches are updated. Required input fields are “slot_Centroid_x”, “slot_Centroid_y”, “slot_Centroid_xErr”, “slot_Centroid_yErr”, and optionally “slot_Centroid_x_y_Cov”. The “coord_ra” and “coord_dec” fields will be updated but are not used as input.- exposure
lsst.afw.image.Exposure
An Exposure or other displayable image on which matches can be overplotted. Ignored (and may be
None
) if display-based debugging is not enabled via lsstDebug.
- matches
- Returns:
- An lsst.pipe.base.Struct with the following fields:
- wcs
lsst.afw.geom.SkyWcs
The best-fit WCS.
- wcs
- scatterOnSky
lsst.geom.Angle
The median on-sky separation between reference objects and sources in “matches”, as an
lsst.geom.Angle
- scatterOnSky
- getFullMetadata() TaskMetadata ¶
Get metadata for all tasks.
- Returns:
- metadata
TaskMetadata
The keys are the full task name. Values are metadata for the top-level task and all subtasks, sub-subtasks, etc.
- metadata
Notes
The returned metadata includes timing information (if
@timer.timeMethod
is used) and any metadata set by the task. The name of each item consists of the full task name with.
replaced by:
, followed by.
and the name of the item, e.g.:topLevelTaskName:subtaskName:subsubtaskName.itemName
using
:
in the full task name disambiguates the rare situation that a task has a subtask and a metadata item with the same name.
- getFullName() str ¶
Get the task name as a hierarchical name including parent task names.
- Returns:
- fullName
str
The full name consists of the name of the parent task and each subtask separated by periods. For example:
The full name of top-level task “top” is simply “top”.
The full name of subtask “sub” of top-level task “top” is “top.sub”.
The full name of subtask “sub2” of subtask “sub” of top-level task “top” is “top.sub.sub2”.
- fullName
- getName() str ¶
Get the name of the task.
- Returns:
- taskName
str
Name of the task.
- taskName
See also
getFullName
Get the full name of the task.
- getTaskDict() dict[str, weakref.ReferenceType[lsst.pipe.base.task.Task]] ¶
Get a dictionary of all tasks as a shallow copy.
- Returns:
- taskDict
dict
Dictionary containing full task name: task object for the top-level task and all subtasks, sub-subtasks, etc.
- taskDict
- classmethod makeField(doc: str) ConfigurableField ¶
Make a
lsst.pex.config.ConfigurableField
for this task.- Parameters:
- doc
str
Help text for the field.
- doc
- Returns:
- configurableField
lsst.pex.config.ConfigurableField
A
ConfigurableField
for this task.
- configurableField
Examples
Provides a convenient way to specify this task is a subtask of another task.
Here is an example of use:
class OtherTaskConfig(lsst.pex.config.Config): aSubtask = ATaskClass.makeField("brief description of task")
- makeInitialWcs(matches, wcs)¶
Generate a guess Wcs from the astrometric matches
We create a Wcs anchored at the center of the matches, with the scale of the input Wcs. This is necessary because the Wcs may have a very approximation position (as is common with telescoped-generated Wcs). We’re using the best of each: positions from the matches, and scale from the input Wcs.
- Parameters:
- matcheslist of
lsst::afw::table::ReferenceMatch
A sequence of reference object/source matches. The following fields are read:
match.first (reference object) coord
match.second (source) centroid
- wcs
lsst::afw::geom::SkyWcs
An initial WCS whose CD matrix is used as the CD matrix of the result.
- matcheslist of
- Returns:
- newWcs
lsst.afw.geom.SkyWcs
A new WCS guess.
- newWcs
- makeSubtask(name: str, **keyArgs: Any) None ¶
Create a subtask as a new instance as the
name
attribute of this task.- Parameters:
- name
str
Brief name of the subtask.
- **keyArgs
Extra keyword arguments used to construct the task. The following arguments are automatically provided and cannot be overridden:
config
.parentTask
.
- name
Notes
The subtask must be defined by
Task.config.name
, an instance ofConfigurableField
orRegistryField
.