add numerical recipes library

lib/nr/ansi/examples/xzrhqr.c

@@ -0,0 +1,30 @@
+
+/* Driver for routine zrhqr */
+
+#include <stdio.h>
+#define NRANSI
+#include "nr.h"
+#include "nrutil.h"
+
+#define M 4     /* degree of polynomial */
+#define MP1 (M+1)   /* no. of polynomial coefficients */
+
+int main(void)
+{
+	static float a[MP1]={-1.0,0.0,0.0,0.0,1.0};
+	float *rti,*rtr;
+	int i;
+
+	rti=vector(1,M);
+	rtr=vector(1,M);
+	printf("\nRoots of polynomial x^4-1\n");
+	printf("\n%15s %15s\n","Real","Complex");
+		zrhqr(a,M,rtr,rti);
+		for (i=1;i<=M;i++) {
+			printf("%5d %12.6f %12.6f\n",i,rtr[i],rti[i]);
+		}
+	free_vector(rtr,1,M);
+	free_vector(rti,1,M);
+	return 0;
+}
+#undef NRANSI