DetectionConfig

class lsst.ip.diffim.DetectionConfig

Bases: lsst.pex.config.Config

Configuration for detecting sources on images for building a PSF-matching kernel

Configuration for turning detected lsst.afw.detection.FootPrints into an acceptable (unmasked, high signal-to-noise, not too large or not too small) list of lsst.ip.diffim.KernelSources that are used to build the Psf-matching kernel

Attributes Summary

badMaskPlanes

Mask planes that lead to an invalid detection.

detOnTemplate

If true run detection on the template (image to convolve); if false run detection on the science image (bool, default True)

detThreshold

Value of footprint detection threshold (float, default 10.0)

detThresholdType

Type of detection threshold (str, default 'pixel_stdev')

fpGrowKernelScaling

If config.scaleByFwhm, grow the footprint based on the final kernelSize.

fpGrowPix

Growing radius (in pixels) for each raw detection footprint.

fpNpixMax

Maximum number of pixels in an acceptable Footprint; too big and the subsequent convolutions become unwieldy (int, default 500)

fpNpixMin

Minimum number of pixels in an acceptable Footprint (int, default 5)

history

scaleByFwhm

Scale fpGrowPix by input Fwhm? (bool, default True)

Methods Summary

compare(other[, shortcut, rtol, atol, output])

Compare this configuration to another Config for equality.

formatHistory(name, **kwargs)

Format a configuration field’s history to a human-readable format.

freeze()

Make this config, and all subconfigs, read-only.

items()

Get configurations as (field name, field value) pairs.

iteritems()

Iterate over (field name, field value) pairs.

iterkeys()

Iterate over field names

itervalues()

Iterate over field values.

keys()

Get field names.

load(filename[, root])

Modify this config in place by executing the Python code in a configuration file.

loadFromStream(stream[, root, filename])

Modify this Config in place by executing the Python code in the provided stream.

names()

Get all the field names in the config, recursively.

save(filename[, root])

Save a Python script to the named file, which, when loaded, reproduces this config.

saveToStream(outfile[, root])

Save a configuration file to a stream, which, when loaded, reproduces this config.

setDefaults()

Subclass hook for computing defaults.

toDict()

Make a dictionary of field names and their values.

update(**kw)

Update values of fields specified by the keyword arguments.

validate()

Validate the Config, raising an exception if invalid.

values()

Get field values.

Attributes Documentation

badMaskPlanes

Mask planes that lead to an invalid detection. Options: NO_DATA EDGE SAT BAD CR INTRP (List, default ('NO_DATA', 'EDGE', 'SAT'))

detOnTemplate

If true run detection on the template (image to convolve); if false run detection on the science image (bool, default True)

detThreshold

Value of footprint detection threshold (float, default 10.0)

detThresholdType

Type of detection threshold (str, default 'pixel_stdev')

Allowed values:

'value'

Use counts as the detection threshold type

'stdev'

Use standard deviation of image plane

'variance'

Use variance of image plane

'pixel_stdev'

Use stdev derived from variance plane

'None'

Field is optional

fpGrowKernelScaling

If config.scaleByFwhm, grow the footprint based on the final kernelSize. Each footprint will be 2*fpGrowKernelScaling*kernelSize x 2*fpGrowKernelScaling*kernelSize. With the value of 1.0, the remaining pixels in each KernelCandiate after convolution by the basis functions will be equal to the kernel size itself. (float, default 1.0)

fpGrowPix

Growing radius (in pixels) for each raw detection footprint. The smaller the faster; however the kernel sum does not converge if the stamp is too small; and the kernel is not constrained at all if the stamp is the size of the kernel. The grown stamp is 2 * fpGrowPix pixels larger in each dimension. This is overridden by fpGrowKernelScaling if scaleByFwhm (int, default 30)

fpNpixMax

Maximum number of pixels in an acceptable Footprint; too big and the subsequent convolutions become unwieldy (int, default 500)

fpNpixMin

Minimum number of pixels in an acceptable Footprint (int, default 5)

history
scaleByFwhm

Scale fpGrowPix by input Fwhm? (bool, default True)

Methods Documentation

compare(other, shortcut=True, rtol=1e-08, atol=1e-08, output=None)

Compare this configuration to another Config for equality.

Parameters
otherlsst.pex.config.Config

Other Config object to compare against this config.

shortcutbool, optional

If True, return as soon as an inequality is found. Default is True.

rtolfloat, optional

Relative tolerance for floating point comparisons.

atolfloat, optional

Absolute tolerance for floating point comparisons.

outputcallable, optional

A callable that takes a string, used (possibly repeatedly) to report inequalities.

Returns
isEqualbool

True when the two lsst.pex.config.Config instances are equal. False if there is an inequality.

Notes

Unselected targets of RegistryField fields and unselected choices of ConfigChoiceField fields are not considered by this method.

Floating point comparisons are performed by numpy.allclose.

formatHistory(name, **kwargs)

Format a configuration field’s history to a human-readable format.

Parameters
namestr

Name of a Field in this config.

kwargs

Keyword arguments passed to lsst.pex.config.history.format.

Returns
historystr

A string containing the formatted history.

freeze()

Make this config, and all subconfigs, read-only.

items()

Get configurations as (field name, field value) pairs.

Returns
itemslist

List of tuples for each configuration. Tuple items are:

  1. Field name.

  2. Field value.

iteritems()

Iterate over (field name, field value) pairs.

Yields
itemtuple

Tuple items are:

  1. Field name.

  2. Field value.

iterkeys()

Iterate over field names

Yields
keystr

A field’s key (attribute name).

itervalues()

Iterate over field values.

Yields
valueobj

A field value.

keys()

Get field names.

Returns
nameslist

List of lsst.pex.config.Field names.

load(filename, root='config')

Modify this config in place by executing the Python code in a configuration file.

Parameters
filenamestr

Name of the configuration file. A configuration file is Python module.

rootstr, optional

Name of the variable in file that refers to the config being overridden.

For example, the value of root is "config" and the file contains:

config.myField = 5

Then this config’s field myField is set to 5.

Deprecated: For backwards compatibility, older config files that use root="root" instead of root="config" will be loaded with a warning printed to sys.stderr. This feature will be removed at some point.

See also

lsst.pex.config.Config.loadFromStream, lsst.pex.config.Config.save, lsst.pex.config.Config.saveFromStream

loadFromStream(stream, root='config', filename=None)

Modify this Config in place by executing the Python code in the provided stream.

Parameters
streamfile-like object, str, or compiled string

Stream containing configuration override code.

rootstr, optional

Name of the variable in file that refers to the config being overridden.

For example, the value of root is "config" and the file contains:

config.myField = 5

Then this config’s field myField is set to 5.

Deprecated: For backwards compatibility, older config files that use root="root" instead of root="config" will be loaded with a warning printed to sys.stderr. This feature will be removed at some point.

filenamestr, optional

Name of the configuration file, or None if unknown or contained in the stream. Used for error reporting.

See also

lsst.pex.config.Config.load, lsst.pex.config.Config.save, lsst.pex.config.Config.saveFromStream

names()

Get all the field names in the config, recursively.

Returns
nameslist of str

Field names.

save(filename, root='config')

Save a Python script to the named file, which, when loaded, reproduces this config.

Parameters
filenamestr

Desination filename of this configuration.

rootstr, optional

Name to use for the root config variable. The same value must be used when loading (see lsst.pex.config.Config.load).

saveToStream(outfile, root='config')

Save a configuration file to a stream, which, when loaded, reproduces this config.

Parameters
outfilefile-like object

Destination file object write the config into. Accepts strings not bytes.

root

Name to use for the root config variable. The same value must be used when loading (see lsst.pex.config.Config.load).

setDefaults()

Subclass hook for computing defaults.

Notes

Derived Config classes that must compute defaults rather than using the Field instances’s defaults should do so here. To correctly use inherited defaults, implementations of setDefaults must call their base class’s setDefaults.

toDict()

Make a dictionary of field names and their values.

Returns
dict_dict

Dictionary with keys that are Field names. Values are Field values.

Notes

This method uses the toDict method of individual fields. Subclasses of Field may need to implement a toDict method for this method to work.

update(**kw)

Update values of fields specified by the keyword arguments.

Parameters
kw

Keywords are configuration field names. Values are configuration field values.

Notes

The __at and __label keyword arguments are special internal keywords. They are used to strip out any internal steps from the history tracebacks of the config. Do not modify these keywords to subvert a Config instance’s history.

Examples

This is a config with three fields:

>>> from lsst.pex.config import Config, Field
>>> class DemoConfig(Config):
...     fieldA = Field(doc='Field A', dtype=int, default=42)
...     fieldB = Field(doc='Field B', dtype=bool, default=True)
...     fieldC = Field(doc='Field C', dtype=str, default='Hello world')
...
>>> config = DemoConfig()

These are the default values of each field:

>>> for name, value in config.iteritems():
...     print(f"{name}: {value}")
...
fieldA: 42
fieldB: True
fieldC: 'Hello world'

Using this method to update fieldA and fieldC:

>>> config.update(fieldA=13, fieldC='Updated!')

Now the values of each field are:

>>> for name, value in config.iteritems():
...     print(f"{name}: {value}")
...
fieldA: 13
fieldB: True
fieldC: 'Updated!'
validate()

Validate the Config, raising an exception if invalid.

Raises
lsst.pex.config.FieldValidationError

Raised if verification fails.

Notes

The base class implementation performs type checks on all fields by calling their validate methods.

Complex single-field validation can be defined by deriving new Field types. For convenience, some derived lsst.pex.config.Field-types (ConfigField and ConfigChoiceField) are defined in lsst.pex.config that handle recursing into subconfigs.

Inter-field relationships should only be checked in derived Config classes after calling this method, and base validation is complete.

values()

Get field values.

Returns
valueslist

List of field values.