MegacamParseTask

class lsst.obs.cfht.ingest.MegacamParseTask(config=None, name=None, parentTask=None, log=None)

Bases: lsst.pipe.tasks.ingest.ParseTask

Attributes Summary

translator_class

Methods Summary

emptyMetadata() Empty (clear) the metadata for this Task and all sub-Tasks.
getAllSchemaCatalogs() Get schema catalogs for all tasks in the hierarchy, combining the results into a single dict.
getDestination(butler, info, filename) Get destination for the file
getExtensionName(md) Get the name of an extension.
getFullMetadata() Get metadata for all tasks.
getFullName() Get the task name as a hierarchical name including parent task names.
getInfo(filename) Get information about the image from the filename and its contents
getInfoFromMetadata(md[, info]) Attempt to pull the desired information out of the header
getName() Get the name of the task.
getSchemaCatalogs() Get the schemas generated by this task.
getTaskDict() Get a dictionary of all tasks as a shallow copy.
makeField(doc) Make a lsst.pex.config.ConfigurableField for this task.
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.
translate_ccd(md)
translate_date(md) Convert a full DATE-OBS to a mere date
translate_defects(md)
translate_filter(md) Translate a full filter description into a mere filter name
translate_taiObs(md)

Attributes Documentation

translator_class = None

Methods Documentation

emptyMetadata()

Empty (clear) the metadata for this Task and all sub-Tasks.

getAllSchemaCatalogs()

Get schema catalogs for all tasks in the hierarchy, combining the results into a single dict.

Returns:
schemacatalogs : dict

Keys are butler dataset type, values are a empty catalog (an instance of the appropriate lsst.afw.table Catalog type) for all tasks in the hierarchy, from the top-level task down through all subtasks.

Notes

This method may be called on any task in the hierarchy; it will return the same answer, regardless.

The default implementation should always suffice. If your subtask uses schemas the override Task.getSchemaCatalogs, not this method.

getDestination(butler, info, filename)

Get destination for the file

@param butler Data butler @param info File properties, used as dataId for the butler @param filename Input filename @return Destination filename

getExtensionName(md)

Get the name of an extension.

Parameters:
md : PropertySet

Metadata to get the name from.

Returns:
name : str or None

Name of the extension if it exists. None otherwise.

getFullMetadata()

Get metadata for all tasks.

Returns:
metadata : lsst.daf.base.PropertySet

The PropertySet keys are the full task name. Values are metadata for the top-level task and all subtasks, sub-subtasks, etc.

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()

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”.
getInfo(filename)

Get information about the image from the filename and its contents

Here, we open the image and parse the header, but one could also look at the filename itself and derive information from that, or set values from the configuration.

Parameters:
filename : str

Name of file to inspect

Returns:
phuInfo : dict

File properties

infoList : list

List of file properties for each extension

getInfoFromMetadata(md, info=None)

Attempt to pull the desired information out of the header

This is done through two mechanisms: * translation: a property is set directly from the relevant header keyword * translator: a property is set with the result of calling a method

The translator methods receive the header metadata and should return the appropriate value, or None if the value cannot be determined.

@param md FITS header @param info File properties, to be supplemented @return info

getName()

Get the name of the task.

Returns:
taskName : str

Name of the task.

See also

getFullName

getSchemaCatalogs()

Get the schemas generated by this task.

Returns:
schemaCatalogs : dict

Keys are butler dataset type, values are an empty catalog (an instance of the appropriate lsst.afw.table Catalog type) for this task.

See also

Task.getAllSchemaCatalogs

Notes

Warning

Subclasses that use schemas must override this method. The default implementation returns an empty dict.

This method may be called at any time after the Task is constructed, which means that all task schemas should be computed at construction time, not when data is actually processed. This reflects the philosophy that the schema should not depend on the data.

Returning catalogs rather than just schemas allows us to save e.g. slots for SourceCatalog as well.

getTaskDict()

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.

classmethod makeField(doc)

Make a lsst.pex.config.ConfigurableField for this task.

Parameters:
doc : str

Help text for the field.

Returns:
configurableField : lsst.pex.config.ConfigurableField

A ConfigurableField for this task.

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")
makeSubtask(name, **keyArgs)

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”.

Notes

The subtask must be defined by Task.config.name, an instance of ConfigurableField or RegistryField.

timer(name, logLevel=10000)

Context manager to log performance data for an arbitrary block of code.

Parameters:
name : str

Name of code being timed; data will be logged using item name: Start and End.

logLevel

A lsst.log level constant.

See also

timer.logInfo

Examples

Creating a timer context:

with self.timer("someCodeToTime"):
    pass  # code to time
translate_ccd(md)
translate_date(md)

Convert a full DATE-OBS to a mere date

Besides being an example of a translator, this is also generally useful. It will only be used if listed as a translator in the configuration.

translate_defects(md)
translate_filter(md)

Translate a full filter description into a mere filter name

Besides being an example of a translator, this is also generally useful. It will only be used if listed as a translator in the configuration.

translate_taiObs(md)