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str_match_ind_regex

Returns a list of indexes into an array of strings that contain the given substring (case sensitive), allowing for regular expressions.

Available in version 6.3.0 and later.

Prototype

	function str_match_ind_regex (
		string_array [*] : string,  
		expression   [1] : string   
	)

	return_val [*] :  integer

Arguments

string_array

A string array of any dimensionality.

expression

The string expression to be matched, with possible regex ("regular expressions") syntax included.

Description

This function returns an array of indexes where every occurrence of expression is matched in string_array. The matching is case sensitive.

Unlike str_match_ind, regular expressions are allowed.

If there is no expression matched in string_array, the default missing value for an integer will be returned.

Note that str_match_ind_regex is case sensitive. Use str_match_ind_ic_regex if you need case insensitivity.

A full description of the syntax and capabilities of regular expressions is beyond the scope of this document. See the Unix/POSIX man page for REGEX (7) or similar documentation for a complete explanation, noting that NCL's implementation uses the "modern" form of regular expressions. In reality only a very small subset of the full functionality will be needed for the purposes of this function.

For those not familiar with the topic one basic point is that unlike the use in a directory listing of the asterisk ('*') as a wildcard standing for any number of arbitrary characters, the equivalent operator in a regular expression consists of the two character sequence: '.*'.

See Also

str_match_regex, str_match_ic_regex, str_match_ind_ic_regex, str_match, str_match_ic, str_match_ind_ic, str_index_of_substr, str_sub_str

Examples

Example 1

Get the indexes of all the strings containing xxLine from the list of strings:

  strings = (/"cnLineColor","mpFillColor","xyLineThicknessF",\
              "txString","polyline"/)
  smatch = str_match_regex(strings,"[a-z][a-z]Line")
  imatch = str_match_ind_regex(strings,"[a-z][a-z]Line")

  print(smatch)
  print(imatch)

Output:

Variable: smatch
Type: string
Total Size: 16 bytes
            2 values
Number of Dimensions: 1
Dimensions and sizes:   [2]
Coordinates: 
(0)     cnLineColor
(1)     xyLineThicknessF

Variable: imatch
Type: integer
Total Size: 8 bytes
            2 values
Number of Dimensions: 1
Dimensions and sizes:   [2]
Coordinates: 
(0)     0
(1)     2