add numerical recipes library

lib/nr/k_and_r/recipes/red.c

@@ -0,0 +1,20 @@
+
+void red(iz1,iz2,jz1,jz2,jm1,jm2,jmf,ic1,jc1,jcf,kc,c,s)
+float ***c,**s;
+int ic1,iz1,iz2,jc1,jcf,jm1,jm2,jmf,jz1,jz2,kc;
+{
+	int loff,l,j,ic,i;
+	float vx;
+
+	loff=jc1-jm1;
+	ic=ic1;
+	for (j=jz1;j<=jz2;j++) {
+		for (l=jm1;l<=jm2;l++) {
+			vx=c[ic][l+loff][kc];
+			for (i=iz1;i<=iz2;i++) s[i][l] -= s[i][j]*vx;
+		}
+		vx=c[ic][jcf][kc];
+		for (i=iz1;i<=iz2;i++) s[i][jmf] -= s[i][j]*vx;
+		ic += 1;
+	}
+}