52 lines
914 B
C
52 lines
914 B
C
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/* Driver for routine pade */
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#include <stdio.h>
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#include <math.h>
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#define NRANSI
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#include "nr.h"
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#include "nrutil.h"
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double fn(double x)
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{
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return (x == 0.0 ? 1.0 : log(1.0+x)/x);
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}
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#define NMAX 100
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int main(void)
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{
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int j,k,n;
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float resid;
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double b,d,fac,x,*c,*cc;
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c=dvector(0,NMAX);
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cc=dvector(0,NMAX);
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for (;;) {
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printf("Enter n for PADE routine:\n");
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if (scanf("%d",&n) == EOF) break;
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fac=1;
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for (j=1;j<=2*n+1;j++) {
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c[j-1]=fac/((double) j);
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cc[j-1]=c[j-1];
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fac = -fac;
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}
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pade(c,n,&resid);
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printf("Norm of residual vector= %16.8e\n",resid);
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printf("point, func. value, pade series, power series\n");
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for (j=1;j<=21;j++) {
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x=(j-1)*0.25;
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for (b=0.0,k=2*n+1;k>=1;k--) {
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b *= x;
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b += cc[k-1];
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}
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d=ratval(x,c,n,n);
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printf("%16.8f %16.8f %16.8f %16.8f\n",x,fn(x),d,b);
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}
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}
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free_dvector(cc,0,NMAX);
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free_dvector(c,0,NMAX);
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return 0;
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}
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#undef NRANSI
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