/* nag_2d_spline_eval_rect(e02dfc) Example Program
 *
 * Copyright 1991 Numerical Algorithms Group.
 *
 * Mark 2, 1991.
 */

#include <nag.h>
#include <stdio.h>
#include <nag_stdlib.h>
#include <nage02.h>

#define MXMAX 20
#define MYMAX 20
#define FF(I,J)  ff[my*(I)+(J)]

  int main(void)
{
  Integer i, j, mx, my;
  double x[MXMAX], y[MYMAX], ff[MXMAX*MYMAX];
  Nag_2dSpline spline;

  Vprintf("e02dfc Example Program Results\n");
  /* Skip heading in data file */
  Vscanf("%*[^\n]");
  /* Read mx and my, the number of grid points in the x and y
   * directions respectively.
   */
  Vscanf("%ld%ld",&mx,&my);
  if (mx<=MXMAX && my<=MYMAX)
    {
      /* Read spline.nx and spline.ny, the number of knots
       * in the x and y directions.
       */
      Vscanf("%ld%ld",&(spline.nx),&(spline.ny));
      spline.c = NAG_ALLOC((spline.nx-4)*(spline.ny-4), double);
      spline.lamda = NAG_ALLOC(spline.nx, double);
      spline.mu = NAG_ALLOC(spline.ny,double);
      if (spline.c != (double *)0 && spline.lamda != (double *)0
          && spline.mu != (double *)0)
        {

          /* Read the knots spline.lamda[0]...spline.lamda[nx-1]
           * and spline.mu[0]...spline.mu[ny-1].
           */
          for (i=0; i<spline.nx;  i++)
            Vscanf("%lf",&(spline.lamda[i]));
          for (i=0; i<spline.ny;  i++)
            Vscanf("%lf",&(spline.mu[i]));
          /* Read spline.c, the bicubic spline coefficients. */
          for (i=0; i<(spline.nx-4)*(spline.ny-4); i++)
            Vscanf("%lf",&(spline.c[i]));
          /* Read the x and y co-ordinates defining the evaluation grid. */
          for (i=0; i<mx;  i++)
            Vscanf("%lf",&x[i]);
          for (i=0; i<my;  i++)
            Vscanf("%lf",&y[i]);
          /* Evaluate the spline at the mx by my points. */
          e02dfc(mx, my, x, y, ff, &spline, NAGERR_DEFAULT);
          /* Print the result array. */
          Vprintf("Spline evaluated on x-y grid (x across, y down):\n      ");
          for (i=0; i<mx;  i++)
            Vprintf("%2.1f      ",x[i]);
          Vprintf("\n");
          for (j=0; j<my; j++)
            {
              Vprintf("%2.1f",y[j]);
              for (i=0; i<mx; i++)
                Vprintf("%8.3f%s",FF(i,j), (i%7==6 || i==mx-1) ? "\n" : " ");
            }
          NAG_FREE(spline.c);
          NAG_FREE(spline.lamda);
          NAG_FREE(spline.mu);
          return EXIT_SUCCESS;
        }
      else
        {
          Vfprintf(stderr,"Storage allocation failed.\n");
          return EXIT_FAILURE;
        }
    }
  else
    {
      Vfprintf(stderr, "mx or my is out of range: mx = %5ld, my = %5ld\n",
               mx,my);
      return EXIT_FAILURE;
    }
}