[Scilab-Dev] floating point operations in different versions of Scilab

[Clément David]

Hello Stéphane,

Sorry for the lag but I tried to investigate a little bit !

Did you try to reproduce on a reduced test case which does not depends
on fsqp ?

For the 5.5.2 release, I did not notice anything that might impact the
behavior of fsqp.

--
Clément

Le lundi 22 juin 2015 à 14:35 +0200, Stéphane Mottelet a écrit :
> Hello Scilab devmasters !
> 
> I have noticed subtle (but real) differences between successive 
> versions 
> of Scilab, here's the whole story:
> 
> I use fsqp to solve an optimization problem where the computation of 
> the 
> cost function and its gradient uses a lot of sparse/full matrix 
> products, and I noticed different convergence behaviour of the same 
> code 
> depending on the Scilab version.
> 
> E.g. with Scilab 5.5.0 and 5.5.1 fsqp converges within the prescribed 
> 
> tolerance (norm of the gradient), but with 5.5.2 fsqp stops its 
> iterations without reaching it. When relaxing the tolerance 
> successful 
> convergence is obtained but I got slightly different results at the 
> end.
> 
> I am wondering about which pathway I should follow to identify the 
> problem, so my questions are the following :
> 
> -is it possible that the scilab version which has been used to 
> compile 
> fsqp could produce such a behaviour ?
> -did the sparse/sparse and sparse/full product routines change 
> recently ?
> 
> Best regards,
> 
> S.
> 
>