6 messages · Angelo Secchi, Roger Bivand, (Ted Harding) +2 more
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? Thanks
======================================================== Angelo Secchi PGP Key ID:EA280337
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().
Thanks
Roger Bivand Economic Geography Section, Department of Economics, Norwegian School of Economics and Business Administration, Helleveien 30, N-5045 Bergen, Norway. voice: +47 55 95 93 55; fax +47 55 95 95 43 e-mail: Roger.Bivand at nhh.no
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) <Ted.Harding at nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 09-Nov-05 Time: 12:25:32 ------------------------------ XFMail ------------------------------
On Wed, 09 Nov 2005 12:25:37 -0000 (GMT)
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.
Thanks. A.
-------------------------------------------------------------------- E-Mail: (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> Fax-to-email: +44 (0)870 094 0861 Date: 09-Nov-05 Time: 12:25:32 ------------------------------ XFMail ------------------------------
======================================================== Angelo Secchi PGP Key ID:EA280337 ======================================================== Current Position: Research Fellow Scuola Superiore S.Anna Piazza Martiri della Liberta' 33, Pisa, 56127 Italy ph.: +39 050 883365 email: secchi at sssup.it www.sssup.it/~secchi/
On Wed, 09 Nov 2005 12:25:37 -0000 (GMT) (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> wrote:
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.
... and this behaviour is OS (or at least command shell specific) for anyone trying this on Windows and wondering why it doesn't work.
Angelo Secchi wrote:
On Wed, 09 Nov 2005 12:25:37 -0000 (GMT) (Ted Harding) <Ted.Harding at nessie.mcc.ac.uk> wrote:
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.
... and this behaviour is OS (or at least command shell specific) for anyone trying this on Windows and wondering why it doesn't work.
But it does work on Windows if you have a reasonable shell. Cmd.exe is and (especially) command.com are not shells in the usually accepted sense. Better to use Rterm than incur the additional overhead of R, though.
Brian D. Ripley, ripley at stats.ox.ac.uk Professor of Applied Statistics, http://www.stats.ox.ac.uk/~ripley/ University of Oxford, Tel: +44 1865 272861 (self) 1 South Parks Road, +44 1865 272866 (PA) Oxford OX1 3TG, UK Fax: +44 1865 272595