/* Driver for routine chebft */#include <stdio.h>#include <math.h>#define NRANSI#include "nr.h"#define NVAL 40#define PIO2 1.5707963float func(float x){	return x*x*(x*x-2.0)*sin(x);}int main(void){	float a=(-PIO2),b=PIO2,dum,f;	float t0,t1,term,x,y,c[NVAL];	int i,j,mval;	chebft(a,b,c,NVAL,func);	/* test result */	for (;;) {		printf("\nHow many terms in Chebyshev evaluation?\n");		printf("Enter n between 6 and %2d. (n=0 to end).\n",NVAL);		scanf("%d",&mval);		if ((mval <= 0) || (mval > NVAL)) break;		printf("\n%9s %14s %16s\n","x","actual","chebyshev fit");		for (i = -8;i<=8;i++) {			x=i*PIO2/10.0;			y=(x-0.5*(b+a))/(0.5*(b-a));			/* Evaluate Chebyshev polynomial without CHEBEV */			t0=1.0;			t1=y;			f=c[1]*t1+c[0]*0.5;			for (j=2;j<mval;j++) {				dum=t1;				t1=2.0*y*t1-t0;				t0=dum;				term=c[j]*t1;				f += term;			}			printf("%12.6f %12.6f %12.6f\n",x,func(x),f);		}	}	return 0;}#undef NRANSI