Name

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    HGREP

Purpose

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      Find a substring in a FITS header (or any other string array)

Calling Sequence

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      HGREP, header, substring, [/KEEPCASE, /LINENUM ]

Inputs

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      header - FITS header or other string array
      substring - scalar string to find in header; if a numeric value is
                supplied, it will be converted to type string

Optional Input Keywords

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      /KEEPCASE: if set, then look for an exact match of the input substring
                Default is to ignore case .
      /LINENUM: if set, prints line number of header in which
                substring appears

Outputs

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      None, results are printed to screen

Example

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      Find every place in a FITS header that the word 'aperture'
      appears in lower case letters and print the element number
      of the header array:
     
      IDL> hgrep, header, 'aperture', /keepcase, /linenum

History

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      Written, Wayne Landsman (Raytheon ITSS) August 1998
      Adapted from STIS version by Phil Plait/ ACC November 14, 1997
      Remove trailing spaces if a non-string is supplied W. Landsman Jun 2002