Is there a bug in gsl_odeiv?

Brian Gough bjg@network-theory.co.uk
Wed Dec 19 13:20:00 GMT 2001


> Is there a bug in gsl_odeiv?

No, there is a bug in your program:

bjg|debian> diff -c ode.c.~1~ ode.c
*** ode.c.~1~   Fri Nov  2 16:37:45 2001
--- ode.c       Fri Nov  2 17:04:17 2001
***************
*** 76,82 ****
  {
    f[0] = y[1];
    f[1] = y[2];
!   f[3] = 1.0;
    return GSL_SUCCESS;
  }
  
--- 76,82 ----
  {
    f[0] = y[1];
    f[1] = y[2];
!   f[2] = 1.0;
    return GSL_SUCCESS;
  }
  
You had me worrried for a few minutes there.  

I recommend using 'checkergcc' to catch problems like that.

For bsimp the jacobian is required, which explains the second problem
you encountered.  In fact, in general it is required (although not
always used).  If there is somewhere in the manual that says otherwise
let me know.

-- 
Brian Gough

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