add numerical recipes library

2025-09-12 18:55:25 +09:00
parent d4dff245bd
commit 2c75620ec9
1344 changed files with 63869 additions and 0 deletions
--- a/lib/nr/cpp/recipes/svdvar.cpp
+++ b/lib/nr/cpp/recipes/svdvar.cpp
@@ -0,0 +1,22 @@
+#include "nr.h"
+
+void NR::svdvar(Mat_I_DP &v, Vec_I_DP &w, Mat_O_DP &cvm)
+{
+	int i,j,k;
+	DP sum;
+
+	int ma=w.size();
+	Vec_DP wti(ma);
+	for (i=0;i<ma;i++) {
+		wti[i]=0.0;
+		if (w[i] != 0.0) wti[i]=1.0/(w[i]*w[i]);
+	}
+	for (i=0;i<ma;i++) {
+		for (j=0;j<i+1;j++) {
+			sum=0.0;
+			for (k=0;k<ma;k++)
+				sum += v[i][k]*v[j][k]*wti[k];
+			cvm[j][i]=cvm[i][j]=sum;
+		}
+	}
+}