IS.NOT.NUMBER

This elegant solution was posted by an astute, anonymous reader:

/TXT?0N


My original solution:

--IS.NOT.NUMBER
--; Input(s): /TXT
--; Output(s): /SKIP as nil
--; If /TXT is not a number return /SKIP as 1.
--0^Q,""^/SKIP,
--DO{(/TXT#Q^/CHR)&(/SKIP_.=.) E(/CHR)^/ASCII,
--IF{/ASCII<46 @SKIP;
--/ASCII>57 @SKIP;
--/ASCII=47 @SKIP},
--Q+1^Q},/SKIP
--
--SKIP
--1^/SKIP