标题: ask for help for prxchange('S/(\()|(\))//',-1,var1) [打印本页] 作者: shiyiming 时间: 2011-9-28 07:38 标题: ask for help for prxchange('S/(\()|(\))//',-1,var1) I am learning PRX and found it is not easy as expected, and hope someone can help.
e.g.:
prxchange('S/(\()|(\))//',-1,var1) (var1: a char variable in the dataset)
in this expression,
(\(): does this mean match with missing value?
|: does this mean 'or' ?
(\): have no idea at all
//: does this mean change to missing vlue?
thanks a lot if someone explain this to me.作者: shiyiming 时间: 2011-9-28 11:28 标题: Re: ask for help for prxchange('S/(\()|(\))//',-1,var1) 我只了解一点正则表达式，我的理解是
\ 是转义字符 比如\( 表示的就是(，因为单独使用(会被当成其他字符。比如\ / ?等都需要\来表达