add numerical recipes library

lib/nr/k_and_r/recipes/addint.c

@@ -0,0 +1,13 @@
+
+void addint(uf,uc,res,nf)
+double **res,**uc,**uf;
+int nf;
+{
+	void interp();
+	int i,j;
+
+	interp(res,uc,nf);
+	for (j=1;j<=nf;j++)
+		for (i=1;i<=nf;i++)
+			uf[i][j] += res[i][j];
+}