ask for help for prxchange('S/(\()|(\))//',-1,var1)

shiyiming

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.

shiyiming

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

/(\()|(\))/ = (|) 也就是匹配左右括号的表达式

"S/(\()|(\))//" = 就是把var1中的括号去掉，你换成这个，估计就可以理解了："S/(\()|(\))/-/"

我也是前不久正弄了个相关的用到的，希望对你有用

shiyiming

thanks a lot.