SAS 9.1 Language Reference Dictionary, Volumes 1, 2 and 3

2017-07-07 02:10:07

Finds the position, length, and score of a substring that matches a pattern

Category: Character String Matching

Restriction: Use with the RXPARSE function

Syntax

CALL RXSUBSTR ( rx, string, position );

CALL RXSUBSTR ( rx, string, position, length );

CALL RXSUBSTR ( rx, string, position, length, score );

Arguments

specifies a numeric value that is returned from the RXPARSE function.

string

specifies the character expression to be searched.

position

specifies a numeric position in a string where the substring that is matched by the pattern begins. If there is no match, the result is zero.

length

specifies a numeric value that is the length of the substring that is matched by the pattern.

score

specifies an integer value based on the number of matches for a particular pattern in a substring.

Details

CALL RXSUBSTR searches the variable string for the pattern from RXPARSE, returns the position of the start of the string, indicates the length of the matched string, and returns a score value. By default, when a pattern matches more than one substring beginning at a specific position, the longest substring is selected.

Comparisons

CALL RXSUBSTR performs the same matching as RXMATCH, but CALL RXSUBSTR additionally allows you to use the length and score arguments to receive more information about the match.

The regular expression (RX) functions and CALL routines work together to manipulate strings that match patterns. Use the RXPARSE function to parse a pattern you specify. Use the RXMATCH function and the CALL RXCHANGE and CALL RXSUBSTR routines to match or modify your data. Use the CALL RXFREE routine to free allocated space.

Example

See the RXPARSE function 'Examples' on page 811.