MathGroup Archive 1996

[Date Index] [Thread Index] [Author Index]

Search the Archive

Re: Using !/bin/command inside a loop

  • To: mathgroup at
  • Subject: [mg5328] Re: Using !/bin/command inside a loop
  • From: "David B. Wagner" <dbwagner at>
  • Date: Wed, 27 Nov 1996 01:47:43 -0500
  • Organization: Principia Consulting
  • Sender: owner-wri-mathgroup at

Sergio Rojas wrote:
> Hello folks;
>            As a single line in any MMa file the line: !/bin/rm filename
>            does its job. However when that line is included in a loop, a
>            While loop for example:
> While[ (Otherset = InputString["New set (no to end)? "]) != "no",
>         !/bin/rm filename  ;
>         n = Input["How many random numbers ?"];
>         Print[Table[Random[],{n}]];
>         % >> filename]
>            the following error message is issued:
> Syntax::sntxf: "        !" cannot be followed by "/bin/rm filename;".
> Could somebody explain the correct use of ! for this particular situation?
> Rojas
> e-mail: sergio at

This is because the "!command" syntax is a hack, not a real Mathematica
expression.  It only works if the ! is the first character in a line,
and probably doesn't work at all when nested inside of another
command.  You should be using the Run or RunThrough commands.


  • Prev by Date: Fractals and/or chaos using MMA v 3.0
  • Next by Date: Re: Single Problem
  • Previous by thread: Using !/bin/command inside a loop
  • Next by thread: help me on this problem