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

[John W. Eaton]

On 21-Apr-2006, Christophe Prud'homme wrote:

| octave2.9:11> which fsolve
| fsolve is the dynamically-linked function from the file
| /usr/lib/octave/2.9.5/oct/i486-pc-linux-gnu/fsolve.oct
| 
| 
| octave-2.1.73:1> which fsolve
| fsolve is the dynamically-linked function from the file
| /usr/lib/octave/2.1.73/oct/i486-pc-linux-gnu/fsolve.oct
| 
| can you reproduce the behavior with your octave installation ?

Yes, but I think there is a simple reason for it.  When you call
fsolve like this:

  w = fsolve (f, x0);

error messages are printed so you won't miss them.  But when you call
fsolve like this:

  [w, info] = fsolve (f, x0);

or

  [w, info, msg] = fsolve (f, x0);

the messages are suppressed because you asked for the status in info
(or info and msg).  Check the value of info (and msg) in the case that
you think is good.  I suspect info is 3 and msg is "iteration is not
making good progress".

jwe