add numerical recipes library

lib/nr/ansi/examples/xftest.c

@@ -0,0 +1,41 @@
+
+/* Driver for routine ftest */
+
+#include <stdio.h>
+#include <math.h>
+#define NRANSI
+#include "nr.h"
+#include "nrutil.h"
+
+#define NPTS 1000
+#define MPTS 500
+#define EPS 0.01
+#define NVAL 11
+
+int main(void)
+{
+	long idum=(-13);
+	int i,j;
+	float f,factor,prob,vrnce,*data1,*data2,*data3;
+
+	data1=vector(1,NPTS);
+	data2=vector(1,MPTS);
+	data3=vector(1,MPTS);
+	/* Generate two gaussian distributions with different variances */
+	printf("\n%16s %5.2f\n","Variance 1 = ",1.0);
+	printf("%13s %11s %16s\n","Variance 2","Ratio","Probability");
+	for (j=1;j<=NPTS;j++) data1[j]=gasdev(&idum);
+	for (j=1;j<=MPTS;j++) data2[j]=gasdev(&idum);
+	for (i=1;i<=NVAL;i++) {
+		vrnce=1.0+(i-1)*EPS;
+		factor=sqrt(vrnce);
+		for (j=1;j<=MPTS;j++) data3[j]=factor*data2[j];
+		ftest(data1,NPTS,data3,MPTS,&f,&prob);
+		printf("%11.4f %13.4f %13.4f\n",vrnce,f,prob);
+	}
+	free_vector(data3,1,MPTS);
+	free_vector(data2,1,MPTS);
+	free_vector(data1,1,NPTS);
+	return 0;
+}
+#undef NRANSI