add numerical recipes library

lib/nr/cpp/recipes/cntab2.cpp

@@ -0,0 +1,51 @@
+#include <cmath>
+#include "nr.h"
+using namespace std;
+
+void NR::cntab2(Mat_I_INT &nn, DP &h, DP &hx, DP &hy, DP &hygx, DP &hxgy,
+	DP &uygx, DP &uxgy, DP &uxy)
+{
+	const DP TINY=1.0e-30;
+	int i,j;
+	DP sum=0.0,p;
+
+	int ni=nn.nrows();
+	int nj=nn.ncols();
+	Vec_DP sumi(ni),sumj(nj);
+	for (i=0;i<ni;i++) {
+		sumi[i]=0.0;
+		for (j=0;j<nj;j++) {
+			sumi[i] += nn[i][j];
+			sum += nn[i][j];
+		}
+	}
+	for (j=0;j<nj;j++) {
+		sumj[j]=0.0;
+		for (i=0;i<ni;i++)
+			sumj[j] += nn[i][j];
+	}
+	hx=0.0;
+	for (i=0;i<ni;i++)
+		if (sumi[i] != 0.0) {
+			p=sumi[i]/sum;
+			hx -= p*log(p);
+		}
+	hy=0.0;
+	for (j=0;j<nj;j++)
+		if (sumj[j] != 0.0) {
+			p=sumj[j]/sum;
+			hy -= p*log(p);
+		}
+	h=0.0;
+	for (i=0;i<ni;i++)
+		for (j=0;j<nj;j++)
+			if (nn[i][j] != 0) {
+				p=nn[i][j]/sum;
+				h -= p*log(p);
+			}
+	hygx=h-hx;
+	hxgy=h-hy;
+	uygx=(hy-hygx)/(hy+TINY);
+	uxgy=(hx-hxgy)/(hx+TINY);
+	uxy=2.0*(hx+hy-h)/(hx+hy+TINY);
+}