Procedure

     REPLCH ( Replace characters in a string )

     SUBROUTINE REPLCH ( INSTR, OLD, NEW, OUTSTR )

Abstract

     Replace all occurrences of a single character with a second
     character.

Required_Reading

     None.

Keywords

     ASCII
     CHARACTER

Declarations

     IMPLICIT NONE

     CHARACTER*(*)    INSTR
     CHARACTER*1      OLD
     CHARACTER*1      NEW
     CHARACTER*(*)    OUTSTR

Brief_I/O

     VARIABLE  I/O  DESCRIPTION
     --------  ---  --------------------------------------------------
     INSTR      I   Input string.
     OLD        I   Character to be replaced.
     NEW        I   Replacement character.
     OUTSTR     O   Output string.

Detailed_Input

     INSTR    is the input character string, possibly containing
              one or more occurrences of the character OLD.

     OLD      is the character to be replaced wherever it occurs in
              the input string.

     NEW      is the character which is to replace each occurrence
              of the character OLD in the output string.

Detailed_Output

     OUTSTR   is the output string. This is the input string
              with every occurrence of the character OLD replaced
              by the character NEW.

              OUTSTR may overwrite INSTR.

Parameters

     None.

Exceptions

     Error free.

Files

     None.

Particulars

     Copy the contents of the input string to the output string
     a character at a time, replacing each occurrence of OLD with NEW.
     If the output string is not long enough to contain the input
     string, it is truncated on the right.

Examples

     Let
           INSTR  = 'Woodsy is the Anti-Pollution Owl.'
           OLD    = 'O'
           NEW    = 'E'
     then
           OUTSTR = 'Woodsy is the Anti-Pollution Ewl.'

     Note the case-sensitivity of REPLCH. The lowercase o's are
     not affected.

     REPLCH may similarly be used to replace control characters
     (such as tab stops, line feeds, and nulls) with regular ASCII
     characters (such as blanks).

Restrictions

     1)  REPLCH is sensitive to case, as shown in the examples above.

Literature_References

     None.

Author_and_Institution

     J. Diaz del Rio    (ODC Space)
     W.L. Taber         (JPL)
     I.M. Underwood     (JPL)

Version

    SPICELIB Version 1.1.0, 12-AUG-2021 (JDR)

        Added IMPLICIT NONE statement.

        Edited the header to comply with NAIF standard.

    SPICELIB Version 1.0.1, 10-MAR-1992 (WLT)

        Comment section for permuted index source lines was added
        following the header.

    SPICELIB Version 1.0.0, 31-JAN-1990 (WLT) (IMU)