From maintainers-request at octave dot org Sun Feb  6 16:48:20 2005
Subject: fsolve Patch for Function Handles
From: Todd Neal <tolchz at tolchz dot net>
To: maintainers at octave dot org
Date: Sun, 6 Feb 2005 17:52:01 -0500

I was looking at the following page http://www.mathworks.com/access/helpdesk/help/toolbox/optim/fsolve.html
and couldn't get this example to work in Octave:


octave:1> x0=2
x0 = 2
octave:2> x = fsolve( at (x)sin(x dot *x),x0)
error: value on right hand side of assignment is undefined
error: evaluating assignment expression near line 2, column 3


I checked and fsolve was not handling parameters that were function
handles correctly, I modified it and it seems to work fine.

octave:1> x0=2
x0 = 2
octave:2>  x = fsolve( at (x)sin(x dot *x),x0)
x = 1.7725


I haven't looked at the code to Octave much in depth so there may 
be a better way to do this or other repercussions from this patch.

Todd




*** a/fsolve.cc 17 Nov 2003 20:19:07 -0000      1.25
--- b/fsolve.cc 6 Feb 2005 22:40:10 -0000
*************** parameters for  at code{fsolve} dot \n\
*** 261,266 ****
--- 261,270 ----
  
        octave_value f_arg = args(0);
  
+       if (f_arg.is_function_handle()) {
+         fsolve_fcn = f_arg.function_value();
+       }
+ 
        switch (f_arg.rows ())
        {
        case 1: