/* FILE NAME: example.c */

/* DESCRIPTION: This "C" program demonstrates the use of a algorithm developed using results of spline curve fit program SplineCurvFit. */

#include "stdio.h"
#include "math.h"

main ()
{

/* Coefficients from output data file (coeff_out) of spline curve fit program. */
/* Coefficients for polynomial form equation y = f(x,z) */
/* 4th order for x and z variation */

double coeff1[16] = {
3.000000e+000, 1.156667e+000, -1.175000e-002, 4.583333e-005, 2.811667e+000,
-1.126667e-001, 1.322917e-003, -4.895833e-006, -3.525000e-002, 1.445833e-003,
-1.734375e-005, 6.510417e-008, -1.416667e-004, 3.541667e-006, -3.385417e-008,
1.302083e-010};

double xval; /* Value of independent variable x */
double yval; /* Value of dependent variable y */
double zval; /* Value of independent variable z */
unsigned char ans; /* Answer to query */

ans = 'y';

while((ans == 'y') || (ans == 'Y')) {

printf ("INPUT INDEPENDANT VARIABLE (xval) = ");
scanf ("%lf", &xval);
printf ("INPUT INDEPENDANT VARIABLE (zval) = ");
scanf ("%lf", &zval);

/* Algorithm for polynomial form equation y = f(x,z) */
/* 4th order for x and z variation */

yval = coeff1[0] + coeff1[1] * zval + coeff1[2] * pow(zval, 2.0) + coeff1[3] * pow(zval, 3.0) + (coeff1[4] + coeff1[5] * zval + coeff1[6] * pow(zval, 2.0) + coeff1[7] * pow(zval, 3.0)) * xval + (coeff1[8] + coeff1[9] * zval + coeff1[10] * pow(zval, 2.0) + coeff1[11] * pow(zval, 3.0)) *
pow(xval, 2.0) + (coeff1[12] + coeff1[13] * zval + coeff1[14] * pow(zval, 2.0) + coeff1[15] *
pow(zval, 3.0)) * pow(xval, 3.0);

printf ("VALUE OF DEPENDENT VARIABLE (yval) = %e\n", yval);

printf ("TO CHECK ADDITIONAL POINTS INPUT y (yes) or n (no) ?");
scanf ("%s", &ans);

}
return 0;
}