add numerical recipes library

lib/nr/ansi/recipes/dsvbksb.c

@@ -0,0 +1,26 @@
+
+#define NRANSI
+#include "nrutil.h"
+
+void dsvbksb(double **u, double w[], double **v, int m, int n, double b[], double x[])
+{
+	int jj,j,i;
+	double s,*tmp;
+
+	tmp=dvector(1,n);
+	for (j=1;j<=n;j++) {
+		s=0.0;
+		if (w[j]) {
+			for (i=1;i<=m;i++) s += u[i][j]*b[i];
+			s /= w[j];
+		}
+		tmp[j]=s;
+	}
+	for (j=1;j<=n;j++) {
+		s=0.0;
+		for (jj=1;jj<=n;jj++) s += v[j][jj]*tmp[jj];
+		x[j]=s;
+	}
+	free_dvector(tmp,1,n);
+}
+#undef NRANSI