pypeit.spectrographs.keck_nirspec module

Module for Keck/NIRSPEC specific methods.

class pypeit.spectrographs.keck_nirspec.KeckNIRSPECLowSpectrograph[source]

Bases: KeckNIRSPECSpectrograph

Child to handle NIRSPEC low-dispersion specific code

comment = 'Low-dispersion grating'

A brief comment or description regarding PypeIt usage with this spectrograph.

name = 'keck_nirspec_low'

The name of the spectrograph. See Spectrographs for the currently supported spectrographs.

supported = True

Flag that PypeIt code base has been sufficiently tested with data from this spectrograph that it is officially supported by the development team.

class pypeit.spectrographs.keck_nirspec.KeckNIRSPECSpectrograph[source]

Bases: Spectrograph

Child to handle Keck/NIRSPEC specific code

bpm(filename, det, shape=None, msbias=None)[source]

Generate a default bad-pixel mask.

Even though they are both optional, either the precise shape for the image (shape) or an example file that can be read to get the shape (filename using get_image_shape()) must be provided.

  • filename (str or None) – An example file to use to get the image shape.

  • det (int) – 1-indexed detector number to use when getting the image shape from the example file.

  • shape (tuple, optional) – Processed image shape Required if filename is None Ignored if filename is not None

  • msbias (numpy.ndarray, optional) – Processed bias frame used to identify bad pixels


An integer array with a masked value set to 1 and an unmasked value set to 0. All values are set to 0.

Return type:


camera = 'NIRSPEC'

Name of the spectrograph camera or arm. This is used by specdb, so use that naming convention

check_frame_type(ftype, fitstbl, exprng=None)[source]

Check for frames of the provided type.


Boolean array with the flags selecting the exposures in fitstbl that are ftype type frames.

Return type:



Return the metadata keys that define a unique instrument configuration.

This list is used by PypeItMetaData to identify the unique configurations among the list of frames read for a given reduction.


List of keywords of data pulled from file headers and used to constuct the PypeItMetaData object.

Return type:


classmethod default_pypeit_par()[source]

Return the default parameters to use for this instrument.


Parameters required by all of PypeIt methods.

Return type:


get_detector_par(det, hdu=None)[source]

Return metadata for the selected detector.

  • det (int) – 1-indexed detector number. This is not used because NIRSPEC only has one detector!

  • hdu (, optional) – The open fits file with the raw image of interest. If not provided, frame-dependent parameters are set to a default.


Object with the detector metadata.

Return type:


header_name = 'NIRSPEC'

Name of the spectrograph camera or arm from the Header. Usually the INSTRUME card.


Define how metadata are derived from the spectrograph files.

That is, this associates the PypeIt-specific metadata keywords with the instrument-specific header cards using meta.

lamps(fitstbl, status)[source]

Check the lamp status.

  • fitstbl (astropy.table.Table) – The table with the fits header meta data.

  • status (str) – The status to check. Can be 'off', 'arcs', or 'dome'.


A boolean array selecting fits files that meet the selected lamp status.

Return type:



ValueError – Raised if the status is not one of the valid options.

ndet = 1

Number of detectors for this instrument.


Define the list of keys to be output into a standard PypeIt file.


The list of keywords in the relevant PypeItMetaData instance to print to the PypeIt Reduction File.

Return type:



Return additional raw header cards to be propagated in downstream output files for configuration identification.

The list of raw data FITS keywords should be those used to populate the configuration_keys() or are used in config_specific_par() for a particular spectrograph, if different from the name of the PypeIt metadata keyword.

This list is used by subheader_for_spec() to include additional FITS keywords in downstream output files.


List of keywords from the raw data files that should be propagated in output files.

Return type:


telescope = Parameter     Value                Default  Type        Callable ---------------------------------------------------------------- name          KECK                 KECK     str         False    longitude     -155.47833333333335  None     int, float  False    latitude      19.828333333333333   None     int, float  False    elevation     4160.000000000756    None     int, float  False    fratio        15                   None     int, float  False    diameter      10                   None     int, float  False    eff_aperture  72.3674              None     int, float  False   

Instance of TelescopePar providing telescope-specific metadata.

url = ''

Reference url