LsstTS8Translator¶

class lsst.obs.lsst.translators.LsstTS8Translator(header, filename=None)¶

Bases: lsst.obs.lsst.translators.lsst.LsstBaseTranslator

Metadata translator for LSST Test Stand 8 data.

Attributes Summary

`DETECTOR_MAX`
`cameraPolicyFile`
`default_resource_package`
`default_resource_root`
`default_search_path`
`detectorMapping`
`detectorSerials`
`name`	Name of this translation class
`supported_instrument`
`translators`

Methods Summary

`are_keys_ok`(keywords)	Are the supplied keys all present and defined?
`can_translate`(header[, filename])	Indicate whether this translation class can translate the supplied header.
`can_translate_with_options`(header, options)	Helper method for `can_translate` allowing options.
`cards_used`()	Cards used during metadata extraction.
`compute_detector_exposure_id`(exposure_id, …)	Compute the detector exposure ID from detector number and exposure ID.
`compute_detector_info_from_serial`(…)	Helper method to return the detector information from the serial.
`compute_detector_num_from_name`(…)	Helper method to return the detector number from the name.
`compute_exposure_id`(dateobs[, seqnum, …])	Helper method to calculate the TS8 exposure_id.
`defined_in_this_class`(name)	Report if the specified class attribute is defined specifically in this class.
`detector_mapping`()	Returns the mapping of full name to detector ID and serial.
`detector_serials`()	Obtain the mapping of detector serial to detector group, name, and number.
`determine_translator`(header[, filename])	Determine a translation class by examining the header
`fix_header`(header, instrument, obsid[, filename])	Apply global fixes to a supplied header.
`is_key_ok`(keyword)	Return `True` if the value associated with the named keyword is present in this header and defined.
`is_keyword_defined`(header, keyword)	Return `True` if the value associated with the named keyword is present in the supplied header and defined.
`is_on_sky`()	Determine if this is an on-sky observation.
`max_detector_exposure_id`()	The maximum detector exposure ID expected to be generated by this instrument.
`max_exposure_id`()	The maximum exposure ID expected from this instrument.
`quantity_from_card`(keywords, unit[, …])	Calculate a Astropy Quantity from a header card and a unit.
`resource_root`()	Package resource to use to locate correction resources within an installed package.
`search_paths`()	Search paths to use for LSST data when looking for header correction files.
`to_altaz_begin`()	Telescope boresight azimuth and elevation at start of observation.
`to_boresight_airmass`()	Airmass of the boresight of the telescope.
`to_boresight_rotation_angle`()	Angle of the instrument in boresight_rotation_coord frame.
`to_boresight_rotation_coord`()	Coordinate frame of the instrument rotation angle (options: sky, unknown).
`to_dark_time`()	Calculate the dark time.
`to_datetime_begin`()
`to_datetime_end`()
`to_detector_exposure_id`()
`to_detector_group`()	Returns the name of the raft.
`to_detector_name`()
`to_detector_num`()
`to_detector_serial`()	Returns the serial number of the detector.
`to_detector_unique_name`()	Return a unique name for the detector.
`to_exposure_group`()	Calculate the exposure group string.
`to_exposure_id`()	Generate a unique exposure ID number
`to_exposure_time`()	Duration of the exposure with shutter open (seconds).
`to_instrument`()	The instrument used to observe the exposure.
`to_location`()	Location of the observatory.
`to_object`()	Object of interest or field name.
`to_observation_counter`()	Return the sequence number within the observing day.
`to_observation_id`()
`to_observation_reason`()
`to_observation_type`()
`to_observing_day`()	Return the day of observation as YYYYMMDD integer.
`to_physical_filter`()	Return the filter name.
`to_pressure`()	Atmospheric pressure outside the dome.
`to_relative_humidity`()	Relative humidity outside the dome.
`to_science_program`()	Observing program (survey or proposal) identifier.
`to_telescope`()	Full name of the telescope.
`to_temperature`()	Temperature outside the dome.
`to_tracking_radec`()	Requested RA/Dec to track.
`to_visit_id`()	Generate a unique exposure ID number
`translator_version`()	Return the version string for this translator class.
`validate_value`(value, default[, minimum, …])	Validate the supplied value, returning a new value if out of range

Attributes Documentation

DETECTOR_MAX = 1000¶

cameraPolicyFile = 'policy/ts8.yaml'¶

default_resource_package = 'astro_metadata_translator'¶

default_resource_root = None¶

default_search_path = None¶

detectorMapping = None¶

detectorSerials = None¶

name = 'LSST-TS8'¶: Name of this translation class

supported_instrument = None¶

translators = {'DECam': <class 'astro_metadata_translator.translators.decam.DecamTranslator'>, 'HSC': <class 'astro_metadata_translator.translators.hsc.HscTranslator'>, 'LSST-TS3': <class 'lsst.obs.lsst.translators.ts3.LsstTS3Translator'>, 'LSST-TS8': <class 'lsst.obs.lsst.translators.ts8.LsstTS8Translator'>, 'LSST-UCDCam': <class 'lsst.obs.lsst.translators.lsst_ucdcam.LsstUCDCamTranslator'>, 'LSSTCam': <class 'lsst.obs.lsst.translators.lsstCam.LsstCamTranslator'>, 'LSSTCam-PhoSim': <class 'lsst.obs.lsst.translators.phosim.LsstCamPhoSimTranslator'>, 'LSSTCam-imSim': <class 'lsst.obs.lsst.translators.imsim.LsstCamImSimTranslator'>, 'LSSTComCam': <class 'lsst.obs.lsst.translators.comCam.LsstComCamTranslator'>, 'LSST_LATISS': <class 'lsst.obs.lsst.translators.latiss.LatissTranslator'>, 'MegaPrime': <class 'astro_metadata_translator.translators.megaprime.MegaPrimeTranslator'>, 'SDSS': <class 'astro_metadata_translator.translators.sdss.SdssTranslator'>, 'SuprimeCam': <class 'astro_metadata_translator.translators.suprimecam.SuprimeCamTranslator'>}¶

Methods Documentation

are_keys_ok(keywords)¶

Are the supplied keys all present and defined?

Parameters:	keywords : iterable of `str` Keywords to test.
Returns:	all_ok : `bool` `True` if all supplied keys are present and defined.

classmethod can_translate(header, filename=None)¶

Indicate whether this translation class can translate the supplied header.

There is no INSTRUME header in TS8 data. Instead we use the TSTAND header. We also look at the file name to see if it starts with “ts8-“.

Older data has no TSTAND header so we must use a combination of headers.

Parameters:	header : `dict`-like Header to convert to standardized form. filename : `str`, optional Name of file being translated.
Returns:	can : `bool` `True` if the header is recognized by this class. `False` otherwise.

classmethod can_translate_with_options(header, options, filename=None)¶

Helper method for can_translate allowing options.

Parameters:	header : `dict`-like Header to convert to standardized form. options : `dict` Headers to try to determine whether this header can be translated by this class. If a card is found it will be compared with the expected value and will return that comparison. Each card will be tried in turn until one is found. filename : `str`, optional Name of file being translated.
Returns:	can : `bool` `True` if the header is recognized by this class. `False` otherwise.

Notes

Intended to be used from within can_translate implementations for specific translators. Is not intended to be called directly from determine_translator.

cards_used()¶

Cards used during metadata extraction.

Returns:	used : `frozenset` of `str` Cards used when extracting metadata.

classmethod compute_detector_exposure_id(exposure_id, detector_num)¶

Compute the detector exposure ID from detector number and exposure ID.

This is a helper method to allow code working outside the translator infrastructure to use the same algorithm.

Parameters:	exposure_id : `int` Unique exposure ID. detector_num : `int` Detector number.
Returns:	detector_exposure_id : `int` The calculated ID.

classmethod compute_detector_info_from_serial(detector_serial)¶

Helper method to return the detector information from the serial.

Parameters:	detector_serial : `str` Detector serial ID.
Returns:	info : `tuple` of (`str`, `str`, `int`) Detector group, name, and number.

classmethod compute_detector_num_from_name(detector_group, detector_name)¶

Helper method to return the detector number from the name.

Parameters:	detector_group : `str` Name of the detector grouping. This is generally the raft name. detector_name : `str` Detector name.
Returns:	num : `int` Detector number.

static compute_exposure_id(dateobs, seqnum=0, controller=None)¶

Helper method to calculate the TS8 exposure_id.

Parameters:	dateobs : `str` Date of observation in FITS ISO format. seqnum : `int`, unused Sequence number. Ignored. controller : `str`, unused Controller type. Ignored.
Returns:	exposure_id : `int` Exposure ID.

classmethod defined_in_this_class(name)¶

Report if the specified class attribute is defined specifically in this class.

Parameters:	name : `str` Name of the attribute to test.
Returns:	in_class : `bool` `True` if there is a attribute of that name defined in this specific subclass. `False` if the method is not defined in this specific subclass but is defined in a parent class. Returns `None` if the attribute is not defined anywhere in the class hierarchy (which can happen if translators have typos in their mapping tables).

Notes

Retrieves the attribute associated with the given name. Then looks in all the parent classes to determine whether that attribute comes from a parent class or from the current class. Attributes are compared using id().

classmethod detector_mapping()¶

Returns the mapping of full name to detector ID and serial.

Returns:	mapping : `dict` of `str`:`tuple` Returns the mapping of full detector name (group+detector) to detector number and serial.
Raises:	ValueError Raised if no camera policy file has been registered with this translation class.

Notes

Will construct the mapping if none has previously been constructed.

classmethod detector_serials()¶

Obtain the mapping of detector serial to detector group, name, and number.

Returns:	info : `dict` of `tuple` of (`str`, `str`, `int`) A `dict` with the serial numbers as keys and values of detector group, name, and number.

classmethod determine_translator(header, filename=None)¶

Determine a translation class by examining the header

Parameters:	header : `dict`-like Representation of a header. filename : `str`, optional Name of file being translated.
Returns:	translator : `MetadataTranslator` Translation class that knows how to extract metadata from the supplied header.
Raises:	ValueError None of the registered translation classes understood the supplied header.

classmethod fix_header(header, instrument, obsid, filename=None)¶

Apply global fixes to a supplied header.

Parameters:	header : `dict` The header to correct. Correction is in place. instrument : `str` The name of the instrument. obsid : `str` Unique observation identifier associated with this header. Will always be provided. filename : `str`, optional Filename associated with this header. May not be set since headers can be fixed independently of any filename being known.
Returns:	modified : `bool` `True` if a correction was applied.

Notes

This method is intended to support major discrepancies in headers such as:

Periods of time where headers are known to be incorrect in some way that can be fixed either by deriving the correct value from the existing value or understanding the that correction is static for the given time. This requires that the date header is known.
The presence of a certain value is always wrong and should be corrected with a new static value regardless of date.

It is assumed that one off problems with headers have been applied before this method is called using the per-obsid correction system.

Usually called from astro_metadata_translator.fix_header.

For log messages, do not assume that the filename will be present. Always write log messages to fall back on using the obsid if filename is None.

is_key_ok(keyword)¶

Return True if the value associated with the named keyword is present in this header and defined.

Parameters:	keyword : `str` Keyword to check against header.
Returns:	is_ok : `bool` `True` if the header is present and not-`None`. `False` otherwise.

static is_keyword_defined(header, keyword)¶

Return True if the value associated with the named keyword is present in the supplied header and defined.

Parameters:	header : `dict`-lik Header to use as reference. keyword : `str` Keyword to check against header.
Returns:	is_defined : `bool` `True` if the header is present and not-`None`. `False` otherwise.

is_on_sky()¶

Determine if this is an on-sky observation.

Returns:	is_on_sky : `bool` Returns True if this is a observation on sky on the summit.

classmethod max_detector_exposure_id()¶

The maximum detector exposure ID expected to be generated by this instrument.

Returns:	max_id : `int` The maximum value.

classmethod max_exposure_id()¶

The maximum exposure ID expected from this instrument.

Returns:	max_exposure_id : `int` The maximum value.

quantity_from_card(keywords, unit, default=None, minimum=None, maximum=None, checker=None)¶

Calculate a Astropy Quantity from a header card and a unit.

Parameters:	keywords : `str` or `list` of `str` Keyword to use from header. If a list each keyword will be tried in turn until one matches. unit : `astropy.units.UnitBase` Unit of the item in the header. default : `float`, optional Default value to use if the header value is invalid. Assumed to be in the same units as the value expected in the header. If None, no default value is used. minimum : `float`, optional Minimum possible valid value, optional. If the calculated value is below this value, the default value will be used. maximum : `float`, optional Maximum possible valid value, optional. If the calculated value is above this value, the default value will be used. checker : `function`, optional Callback function to be used by the translator method in case the keyword is not present. Function will be executed as if it is a method of the translator class. Running without raising an exception will allow the default to be used. Should usually raise `KeyError`.
Returns:	q : `astropy.units.Quantity` Quantity representing the header value.
Raises:	KeyError The supplied header key is not present.

resource_root()¶

Package resource to use to locate correction resources within an installed package.

Returns:	resource_package : `str` Package resource name. `None` if no package resource are to be used. resource_root : `str` The name of the resource root. `None` if no package resources are to be used.

search_paths()¶

Search paths to use for LSST data when looking for header correction files.

Returns:	path : `list` List with a single element containing the full path to the `corrections` directory within the `obs_lsst` package.

to_altaz_begin()¶

Telescope boresight azimuth and elevation at start of observation.

Returns:	translation : `astropy.coordinates.AltAz` Translated property.

to_boresight_airmass()¶

Airmass of the boresight of the telescope.

Returns:	translation : `float` Translated property.

to_boresight_rotation_angle()¶

Angle of the instrument in boresight_rotation_coord frame.

Returns:	translation : `astropy.coordinates.Angle` Translated property.

to_boresight_rotation_coord()¶

Coordinate frame of the instrument rotation angle (options: sky, unknown).

Returns:	translation : `str` Translated property.

to_dark_time()¶

Calculate the dark time.

If a DARKTIME header is not found, the value is assumed to be identical to the exposure time.

Returns:	dark : `astropy.units.Quantity` The dark time in seconds.

to_datetime_begin()¶

to_datetime_end()¶

to_detector_exposure_id()¶

to_detector_group()¶

Returns the name of the raft.

Extracted from RAFTNAME header.

Raftname should be of the form: ‘LCA-11021_RTM-011-Dev’ and the resulting name will have the form “RTM-NNN”.

Returns:	name : `str` Name of raft.

to_detector_name()¶

to_detector_num()¶

to_detector_serial()¶

Returns the serial number of the detector.

Returns:	serial : `str` LSST assigned serial number.

Notes

This is the LSST assigned serial number (LSST_NUM), and not the manufacturer’s serial number (CCD_SERN).

to_detector_unique_name()¶

Return a unique name for the detector.

Base class implementation attempts to combine detector_name with detector_group. Group is only used if not None.

Can be over-ridden by specialist translator class.

Returns:	name : `str` detector_group``_``detector_name if `detector_group` is defined, else the `detector_name` is assumed to be unique. If neither return a valid value an exception is raised.
Raises:	NotImplementedError Raised if neither detector_name nor detector_group is defined.

to_exposure_group()¶

Calculate the exposure group string.

For LSSTCam and LATISS this is read from the GROUPID header. If that header is missing the exposure_id is returned instead as a string.

to_exposure_id()¶

Generate a unique exposure ID number

Note that SEQNUM is not unique for a given day in TS8 data so instead we convert the ISO date of observation directly to an integer.

Returns:	exposure_id : `int` Unique exposure number.

to_exposure_time()¶

Duration of the exposure with shutter open (seconds).

Returns:	translation : `astropy.units.Quantity` Translated value derived from the header.

to_instrument()¶

The instrument used to observe the exposure.

Returns:	translation : `str` Translated property.

to_location()¶

Location of the observatory.

Returns:	translation : `astropy.coordinates.EarthLocation` Translated property.

to_object()¶

Object of interest or field name.

Returns:	translation : `str` Translated property.

to_observation_counter()¶

Return the sequence number within the observing day.

Returns:	counter : `int` The sequence number for this day.

to_observation_id()¶

to_observation_reason()¶

to_observation_type()¶

to_observing_day()¶

Return the day of observation as YYYYMMDD integer.

For LSSTCam and other compliant instruments this is the value of the DAYOBS header.

Returns:	obs_day : `int` The day of observation.

to_physical_filter()¶

Return the filter name.

Uses the FILTPOS header.

Returns:	filter : `str` The filter name. Returns “NONE” if no filter can be determined.

Notes

The calculations here are examples rather than being accurate. They need to be fixed once the camera acquisition system does this properly.

to_pressure()¶

Atmospheric pressure outside the dome.

Returns:	translation : `astropy.units.Quantity` Translated property.

to_relative_humidity()¶

Relative humidity outside the dome.

Returns:	translation : `float` Translated property.

to_science_program()¶

Observing program (survey or proposal) identifier.

Returns:	translation : `str` Translated value derived from the header.

to_telescope()¶

Full name of the telescope.

Returns:	translation : `str` Translated property.

to_temperature()¶

Temperature outside the dome.

Returns:	translation : `astropy.units.Quantity` Translated property.

to_tracking_radec()¶

Requested RA/Dec to track.

Returns:	translation : `astropy.coordinates.SkyCoord` Translated property.

to_visit_id()¶

Generate a unique exposure ID number

Note that SEQNUM is not unique for a given day in TS8 data so instead we convert the ISO date of observation directly to an integer.

Returns:	exposure_id : `int` Unique exposure number.

classmethod translator_version()¶

Return the version string for this translator class.

Returns:	version : `str` String identifying the version of this translator.

Notes

Assumes that the version is available from the __version__ variable in the parent module. If this is not the case a translator should subclass this method.

static validate_value(value, default, minimum=None, maximum=None)¶

Validate the supplied value, returning a new value if out of range

Parameters:

value : float: Value to be validated.
default : float: Default value to use if supplied value is invalid or out of range. Assumed to be in the same units as the value expected in the header.
minimum : float: Minimum possible valid value, optional. If the calculated value is below this value, the default value will be used.
maximum : float: Maximum possible valid value, optional. If the calculated value is above this value, the default value will be used.

Returns:

value : float: Either the supplied value, or a default value.

Navigation

LsstTS8Translator¶