#include <stdio.h>
#include <math.h>
#include "genlib.h"


/*spherical covariance function*/
double spherical(double h)
{
  double z;

  if (h >= 1.) {
    z = 0.;
  } else {
    z = 1.-1.5*(double)h+0.5*(double)(h*h*h);
  }
  return (z);
}