December 11, 2013

About This Article

This describes changes from calcos version 2.19.6 to 2.20.1.

Relevant Trac Tickets and PRs
Trac PR Update
718 68538 Update deprecated Python syntax in calcos.
735 68712 Change calcos import statements for boxcar.
961 72796 Calcos gives the wrong EXPTIME in x1dsum for NUV.
973 73085 Calcos should check wavecorr before updating WAVECALS.
981 73424 Calcos should use a SEARCH_OFFSET column in the WCPTAB.
982 73439 Calcos should allow aperture = "N/A".
984 73571 Calcos x1dsum files have DQ = 0 for some bad pixels.
988 73686 Calcos should import pyfits from astropy.
995 74005 Function in calcos gets DETECTOR from wrong header.
1001 74177 Calcos should check that EXPEND - EXPSTART is not zero.
1019 75005 Have CalCOS check the exposure time (EXPTIME) before the CSUMs are created


  • For NUV x1dsum and x1dsum1-4 files, the EXPTIME keyword was being populated with a value that was three times too large.  This has been fixed.
  • There were situations where a bad pixel in an x1dsum file was not flagged as bad in the DQ column; this has been fixed.
  • Some exposures have the same values for EXPSTART and EXPEND, even though the exposure time is not really zero.  For these exposures, calcos was dividing by zero.  A check for this case has been added.
  • A dark exposure may have aperture = N/A and/or life_adj = -999.
  • The exposure time keyword(s) are now updated just before writing the "calcos sum" (csum) file, in case calcos does not finish processing due to a bad value for the APERTURE keyword or a missing reference file.
  • A new column is supported for the wavecal parameters table, allowing an offset to the search range for a wavecal spectrum.
  • The WAVECALS keyword was sometimes set to a value (the name of a file) even if wavecal processing was not actually done.


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