topic Re: Prxchange understanding in SAS Programming

Prxchange understanding

David_Billa — Tue, 16 Aug 2022 13:24:05 GMT

can someone help me understand this line?

MAT_NBR= prxchange('s/^(0*)//', -1,NBR);

Re: Prxchange understanding

kelxxx — Tue, 16 Aug 2022 14:04:36 GMT

Unless I am mistaken,

mat_nbr = remove the Matched Pattern in variable NBR , the value of times is –1, then matching patterns continue to be replaced until the end of source is reached.

Sequence: match all of the followings in order
BeginOfLine
CapturingGroup
GroupNumber:1
Repeat
0
zero or more times

=>>> remove Leading Zeros in the varible nbr

nbr = 0001 => mat_nbr=1

nbr= 001 01 => mat_nbr=1 01

Re: Prxchange understanding

PGStats — Tue, 16 Aug 2022 19:32:39 GMT

The function call removes leading zeros if starting at the first character. Is equivalent to prxchange("s/^0+//", 1, NBR). Note that prxchange("s/^\s*0+//", 1, NBR) would account for leading spaces.