#include 
#include 
#include "assert.h"

#define SIZE 10000

shape [SIZE] span;

double fabs(double);

main ()
{
   double sum;                 /* Sum of areas */
   double width;
   double:span x;              /* Midpoint of rectangle on x axis */

    x = (pcoord (span,0)+0.5) * 1.0 / SIZE;
    sum = (+= (4.0/(1.0+x*x)));

   sum *= 1.0/SIZE;

   printf ("Estimation of pi is %14.12f\n", sum);

   assert (fabs (sum - 3.141592) < 0.00001);
}

  ...
 dpce_descriptor_t span;
 int vdpc_span = 0;
 double fabs(double );
 main( )
 {
    int j1, *j2, j3, j4;
    float r1, r2;
    double d1;
    double sum;
    double width;
    double x[10000];
    if ( !vdpc_span )
    {
          vdpc_init_desc( &span, 3,1,10000,10000,1 );
          vdpc_span = 1;
    }
    r1 = 1.F / 10000;
    r2 = 0.;
    for ( j1=0; j1 < 10000; j1++ )
    {
          x[j1] = ((r2 + 0.5) * 1.0) * r1;
          r2 = r2 + 1.;
    }
    d1 = 0;
       for ( j1=0; j1 <= 9999; j1 += 1 )
       d1 = d1 + 4.0 / (1.0 + x[j1] * x[j1]);
    sum = d1;
    sum *= 1.0 / 10000;
    printf( "Estimation of pi is %14.12f\n", sum );
    fabs( sum - 3.141592 ) < 0.00001 ? (void )0 : _assert( 
    "fabs (sum - 3.141592) < 0.00001", "pi.dpc",25 );
 }