odeiv_evolve_apply returns final value different than input

[James <james dot umbanhowar at mcgill dot ca>]

Hello,
I'm trying to get evenly spaced samples from the adaptive step side 
integrator as suggested in the manual.  however, the value t returned 
from gsl_odeiv_evolve_apply as the final value is 1x10-18 less than ti. 
 I've developed an inelegant workaround but was wondering why this was 
happening?  Is this a problem of different sized doubles?

For example, when i run the code at bottom i get out puts for  h (step 
size), t (time) - ti (final time)
of:
0.000000e+00  -6.938894e-18

Thanks for any help,
James Umbanhowar


All variables in the code are doubles.

      ti = 0;
      while(ti<max(20/params[1],params[5]*1000))   \\loop until time 
max(...,...)
    {

      ti += params[5];  \\data output step size
      while (t < ti)
        {
         gsl_odeiv_evolve_apply (e, c, s,&sys,&t, ti, &h,y);
          printf("%e %e %.3e\n",h,t<ti,t-ti,);
        }
          fprintf(datafile,"%.3f %.3f \n",ti,y[0]-y[1]);
    }