From help-request at octave dot org Thu Jan 20 17:23:02 2005
Subject: Octave's eval function
From: "E. Joshua Rigler" <Jrigler at colorado dot edu>
To: Help-Octave <help at octave dot org>
Date: Thu, 20 Jan 2005 16:23:43 -0700

The following does what I want:

  out=eval("if (~exist('tmp')) tmp=0; endif; tmp=tmp+1; tmp*5;");

...specifically, it evaluates the string to 1) initialize the variable
tmp if it doesn't already exist; 2) increment tmp by 1 each time it is
called; and 3) return tmp*5 to the variable out.

Is the fact that eval appears to always return the result of the last
expression in the string (i.e., tmp*5) strictly intentional?  I can't
really tell from the help file.  This is exactly what I want, but I just
want to be sure this behavior isn't likely to change anytime soon.

I'm running 2.1.64 with the latest Forge.  Thanks,

EJR



-------------------------------------------------------------
Octave is freely available under the terms of the GNU GPL.

Octave's home on the web:  http://www.octave.org
How to fund new projects:  http://www.octave.org/funding.html
Subscription information:  http://www.octave.org/archive.html
-------------------------------------------------------------