add numerical recipes library

lib/nr/ansi/examples/xzroots.c

@@ -0,0 +1,45 @@
+
+/* Driver for routine zroots */
+
+#include <stdio.h>
+#define NRANSI
+#include "nr.h"
+#include "complex.h"
+
+#define M 4
+#define MP1 (M+1)
+#define TRUE 1
+#define FALSE 0
+
+int main(void)
+{
+	int i,polish;
+	fcomplex roots[MP1];
+	static fcomplex a[MP1]={{0.0,2.0},
+				{0.0,0.0},
+				{-1.0,-2.0},
+				{0.0,0.0},
+				{1.0,0.0} };
+
+	printf("\nRoots of the polynomial x^4-(1+2i)*x^2+2i\n");
+	polish=FALSE;
+	zroots(a,M,roots,polish);
+	printf("\nUnpolished roots:\n");
+	printf("%14s %13s %13s\n","root #","real","imag.");
+	for (i=1;i<=M;i++)
+		printf("%11d %18.6f %12.6f\n",i,roots[i].r,roots[i].i);
+	printf("\nCorrupted roots:\n");
+	for (i=1;i<=M;i++)
+		roots[i]=RCmul(1+0.01*i,roots[i]);
+	printf("%14s %13s %13s\n","root #","real","imag.");
+	for (i=1;i<=M;i++)
+		printf("%11d %18.6f %12.6f\n",i,roots[i].r,roots[i].i);
+	polish=TRUE;
+	zroots(a,M,roots,polish);
+	printf("\nPolished roots:\n");
+	printf("%14s %13s %13s\n","root #","real","imag.");
+	for (i=1;i<=M;i++)
+		printf("%11d %18.6f %12.6f \n",i,roots[i].r,roots[i].i);
+	return 0;
+}
+#undef NRANSI