add numerical recipes library

lib/nr/ansi/examples/xfleg.c

@@ -0,0 +1,33 @@
+
+/* Driver for routine fleg */
+
+#include <stdio.h>
+#define NRANSI
+#include "nr.h"
+#include "nrutil.h"
+
+#define NVAL 5
+#define DX 0.2
+#define NPOLY 5
+
+int main(void)
+{
+	int i,j;
+	float x,*afunc;
+
+	afunc=vector(1,NPOLY);
+	printf("\n%3s\n","Legendre polynomials");
+	printf("%9s %9s %9s %9s %9s\n","n=1","n=2","n=3","n=4","n=5");
+	for (i=1;i<=NVAL;i++) {
+		x=i*DX;
+		fleg(x,afunc,NPOLY);
+		printf("x =%5.2f\n",x);
+		for (j=1;j<=NPOLY;j++) printf("%10.4f",afunc[j]);
+		printf("  routine FLEG\n");
+		for (j=1;j<=NPOLY;j++) printf("%10.4f",plgndr(j-1,0,x));
+		printf("  routine PLGNDR\n\n");
+	}
+	free_vector(afunc,1,NPOLY);
+	return 0;
+}
+#undef NRANSI