Hi Jim, What you told me works well.
I have tried using 'eval(parse(text="1:20 = x"))' as well as 'try(parse(text="1:20 = x"))' before but not using eval anfd try functions together. I just added try function following your suggestion, e.g. 'try(eval(parse(text="1:20 = x")))'and then it worked well. Thank you very much for the nice and instant help. Howard On Wed Oct 10 10:02:39 EDT 2007, jim holtman <[EMAIL PROTECTED]> wrote: > You need to follow the posting guide and provide commented, > minimal, > self-contained, reproducible code. > > I can only guess at what your code looks like, but the following > catches the error: > >> z <- try(eval(parse(text="1:20 <- x"))) > Error in eval(expr, envir, enclos) : object "x" not found >> str(z) > Class 'try-error' chr "Error in eval(expr, envir, enclos) : > object > \"x\" not found\n" >> z <- try(eval(parse(text="x <- 1:20"))) >> str(z) > int [1:20] 1 2 3 4 5 6 7 8 9 10 ... >> > > > On 10/10/07, HU,ZHENGJUN <[EMAIL PROTECTED]> wrote: >> Hi All, >> >> I entered a R statement, e.g. 1:20 = x or log("a") on an HTML >> form and passed it to a R-CGI script. Obviously, neither of both >> is a correct R statement or expression. However, my R-CGI script >> could not return and report the error message to the Web site >> even >> though it received the statement. I tried to use some R built-in >> functions of try, tryCatch, eval, expression, as.expression, >> parse, deparse, etc. None of them worked. >> >> Note: when a statement is correct, i.e. x = 1:20 or log(2), the >> same script returned and reported the R output to the Web site. >> >> If any of you has the experience about the matter or topic, >> could you please tell me how to catch a R error in this case? >> >> Thank you very much for the help in advance. >> Howard >> >> ______________________________________________ >> R-help@r-project.org mailing list >> https://stat.ethz.ch/mailman/listinfo/r-help >> PLEASE do read the posting guide >> http://www.R-project.org/posting-guide.html >> and provide commented, minimal, self-contained, reproducible >> code. >> > > > -- Jim Holtman > Cincinnati, OH > +1 513 646 9390 > > What is the problem you are trying to solve? > > -- HU,ZHENGJUN ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.