On 09-Nov-05 Roger Bivand wrote: > On Wed, 9 Nov 2005, Angelo Secchi wrote: >> Hi, >> I wrote a small R script (delta.R) using commandArgs(). The script >> works from the shell in usual way >> >> R --no-save arg1 < delta2.R >> >> Suppose arg1 is the output of another shell command (e.g. gawk, >> sed ...). Is there a way to tell R to read arg1 from the >> output of the previous command? Any other workaround? > > Use shell variables, possibly also Sys.getenv() within R as well as or > instead of commandArgs().
If it's a fairly simple shell comand (and even if it isn't, though it could get tricky for complicated ones) you can use the "backquote" trick (called, in well-spoken circles, "command substitution"): R --no-save `shellcmd` < delta2.R As in all shell command lines, wherever you have a command (including arguments etc.) between backquotes, as exemplified by "`shellcmd`" above, the output of the command (as sent to stdout) replaces "`shellcmd`" in the command-line. This could be a lot of stuff (depending on what "shellcmd" is), or just one value, or whatever. Best wishes, Ted. -------------------------------------------------------------------- E-Mail: (Ted Harding) <[EMAIL PROTECTED]> Fax-to-email: +44 (0)870 094 0861 Date: 09-Nov-05 Time: 12:25:32 ------------------------------ XFMail ------------------------------ ______________________________________________ R-help@stat.math.ethz.ch mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide! http://www.R-project.org/posting-guide.html
