Re: bug in fsolve() affecting convergence depending on the returned args

[John W. Eaton]

On 26-Apr-2006, Christophe Prud'homme wrote:

| I modified the script as you proposed (check info on return for the "good" 
| case) but without success

I think you did not modify the code in the way I suggested.  Your
check of info is not the same:

|     if (~info)
|       error(msg);
|     end

My patch had the lines

+    if (info != 1)
+      error (msg);
+    end

Please try that and see what results you obtain.

The values that fsolve returns in info are:

  1: solution converged within specified tolerance
  2: number of function calls exceeded limit
  3: no further improvement possible (tolerance may be too small)
  4: iteration is not making good progress

(Unfortunately, I think this is not documented in the fsolve help;
patches anyone?)

jwe