fsolve() nasty bug ?

[Christophe Prud'homme]

Hi 

while writing an octave/matlab compatible Crank Nicolson routine,
I came up with, I believe, an fsolve issue.
Please see the cranknic.m file attached and corresponding test 
cranknic_test2.m that check the error for an ode system

If I write 

w = fsolve( 'myfun', the_y );

then fsolve does not converge

If I write 

[w info msg] = fsolve( 'myfun', the_y );

then fsolve _does_ converge. Actually returning just info is sufficient to 
make fsolve() work.

I suspect there is a nasty bug somewhere in the implementation of fsolve(), 
that is disabled when some extra arguments are returned by fsolve().

any comments ?

PS : I have tested this with 2.1.73 and 2.9.5


Best regards
C.
-- 
Christophe Prud'homme
EPFL SB IACS CMCS
MA B2 534 (Bâtiment MA)
Station 8
CH-1015 Lausanne
Tel: +41 (0)21 693 25 47
Fax: +41 (0)21 693 43 03

cranknic.m
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cranknic_test2.m
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