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Command line method

You can combine your IDF files from the command line with idf_combine.

Usage:
  idf_combine [-ahbc]  [-v level] output_idf_file input_idf_files

Options:
  -h:  this help message
  -v:  verbosity level (=1; 0 is silent)
  -a:  ignore EXP_STAT keyword 
  -c:  recalculates Y centroids (use target events) 
  -b:  store ORBITAL_VEL in a float

Here is how to combine all exposures of observation M1010101 for segment 2A.

  idf_combine -c  M1010101all2attagfidf.fit M1010101*2attagfidf.fit

Without the c switch, the Y centroid of the LiF and SiC target apertures wouldn't be re-calculated. The EXP_ID keyword in the main header of the output file is set to '999'. Thus after extraction, you will get the two files:

  M10101019992alifttagfcal.fit
  M10101019992asicttagfcal.fit

The a switch makes the program ignore the EXP_STAT keyword. This means that exposures that have EXP_STAT strictly positive will not be rejected as would be the case without the a switch. The EXP_STAT keyword is set to a strictly postive value by the pipeline if the exposure is bad or for histogram (HIST) files that contain bursts, SAA crossing or low limb angle: these exposures contain many bad events that cannot be screened because HIST files are not time-tagged.

The b switch will be discussed later.



Bernard Godard 2004-11-04