STRSUBST Function

Performs search and replace string substitution.

Discussion

NOTE: STRSUBST uses regular expressions, not wildcard characters, for pattern matching. To use STRSUBST, it is crucial that you understand regular expressions. For a detailed discussion of regular expressions, see the chapter Working with Text in the PV-WAVE Programmer's Guide.

By default, only the first occurrence of pattern is replaced. Use the Global keyword to replace all occurrences of pattern.

Example 1

In this example, a list of .pro files is converted to .cpr files.

source = 'foo.pro, bar.pro'
cprfiles = STRSUBST(source, 'pro', 'cpr', $
/Global)

; The letters "pro" are replaced by "cpr".

PRINT, cprfiles

foo.cpr, bar.cpr

Example 2

Suppose that you wish to change the file extension in the following string from .pp to .dat.

str1='$MDATA/ppt/thefile.pp'

You might try the following STRSUBST command:

str2=STRSUBST(str1, '.pp', '.dat'

Unfortunately, this command returns the following string, which is not the desired result:

PRINT, str2
$MYDATA/.datt/thefile.pp

The reason for this is that the pattern expression, '.pp', contains the regular expression special character . (dot), which means "match any single character except newline". One way to obtain the correct result is to "escape" this special character with the backslash (\), as follows:

str2=STRSUBST(str1, '\\.pp', '.dat') 
PRINT, str2
$MYDATA/ppt/thefile.dat

NOTE: Two backslashes are needed because in PV-WAVE strings, you need a pair of backslashes to make a single backslash. For more information on this subject, see the chapter Working with Text in the PV-WAVE Programmer's Guide.

STRSUBST Function

Usage

Input Parameters

Returned Value

Keywords

Discussion

Example 1

Example 2

See Also