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Index Page ncposr_c

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Procedure Abstract Required_Reading Keywords Brief_I/O Detailed_Input | Detailed_Output Parameters Exceptions Files Particulars Examples | Restrictions Literature_References Author_and_Institution Version Index_Entries

#### Procedure

       ncposr_c ( Character position, reverse )

       SpiceInt ncposr_c ( ConstSpiceChar    * str,
                           ConstSpiceChar    * chars,
                           SpiceInt            start  )

#### Abstract

       Find the first occurrence in a string of a character NOT belonging
       to a collection of characters, starting at a specified location,
       searching in reverse.

#### Required_Reading

       SCANNING

#### Keywords

       CHARACTER
       SEARCH
       UTILITY

#### Brief_I/O

       VARIABLE  I/O  DESCRIPTION
       --------  ---  --------------------------------------------------
       str        I   Any character string.
       chars      I   A collection of characters.
       start      I   Position to begin looking for one of chars.

       The function returns the index of the last character of str
       at or before index start that is not in the collection chars.

#### Detailed_Input

       str         is any character string.

       chars       is a character string containing a collection
                   of characters. Spaces in chars are significant,
                   including trailing blanks. The order in which
                   characters are listed is not significant.

       start       is the position in str to begin looking for one of
                   the characters in chars. start may range from 0
                   to n-1, where n is the number of characters in str.

#### Detailed_Output

       The function returns the index of the last character of str (at or
       before index start) that is not one of the characters in the string
       chars. The returned value normally ranges from 0 to n-1, where n is
       the number of characters in str. If none of the characters is found,
       the function returns -1.

#### Parameters

       None.

#### Exceptions

       1)  If `start' is less than 0, ncposr_c returns -1.

       2)  If `start' is greater than strlen(str), the search begins
           at the last character of the string.

       3)  If any of the `str' or `chars' input string pointers is null,
           the error SPICE(NULLPOINTER) is signaled. The function returns
           the value -1.

       4)  If any of the `str' or `chars' input string has zero length,
           the function returns the value -1. This case is not considered
           an error.

#### Files

       None.

#### Particulars

       ncposr_c is case sensitive.

       An entire family of related CSPICE routines

          cpos_c
          cposr_c
          ncpos_c
          ncposr_c
          pos_c
          posr_c

       is described in the Required Reading.

#### Examples

       Let string == "BOB, JOHN, TED, AND MARTIN...."
                      012345678901234567890123456789

       Let chars  == "ABCDEFGHIJKLMNOPQRSTUVWXYZ"

       Normal (sequential) searching:
       ------------------------------

         ncposr_c( string, ' ,',    29 ) = 29
         ncposr_c( string, ' ,',    28 ) = 28
         ncposr_c( string, ' ,',    27 ) = 27
         ncposr_c( string, ' ,',    26 ) = 26
         ncposr_c( string, ' ,',    25 ) = 19
         ncposr_c( string, ' ,',    18 ) = 15
         ncposr_c( string, ' ,',    14 ) = 14
         ncposr_c( string, ' ,',    13 ) = 10
         ncposr_c( string, ' ,',     9 ) =  9
         ncposr_c( string, ' ,',     8 ) =  4
         ncposr_c( string, ' ,',     3 ) =  3
         ncposr_c( string, ' ,',     2 ) = -1

       start out of bounds:
       --------------------

         ncposr_c( string, ' ,',    -1 ) = -1
         ncposr_c( string, ' ,',    -5 ) = -1
         ncposr_c( string, ' ,',    30 ) = 29
         ncposr_c( string, ' ,',   122 ) = 29

#### Restrictions

       None.

#### Literature_References

       None.

#### Author_and_Institution

       N.J. Bachman        (JPL)
       J. Diaz del Rio     (ODC Space)
       W.L. Taber          (JPL)

#### Version

       -CSPICE Version 1.0.1, 04-AUG-2021 (JDR)

           Edited the header to comply with NAIF standard.

       -CSPICE Version 1.0.0, 27-AUG-2002 (NJB) (WLT)

#### Index_Entries

       backward search for position of unlisted character

#### Link to routine ncposr_c source file ncposr_c.c

    Fri Dec 31 18:41:10 2021