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/irbit2.cpp
+++ b/lib/nr/cpp/recipes/irbit2.cpp
@@ -0,0 +1,15 @@
+#include "nr.h"
+
+int NR::irbit2(unsigned long &iseed)
+{
+	const unsigned long IB1=1,IB2=2,IB5=16,IB18=131072;
+	const unsigned long MASK=IB1+IB2+IB5;
+
+	if (iseed & IB18) {
+		iseed=((iseed ^ MASK) << 1) | IB1;
+		return 1;
+	} else {
+		iseed <<= 1;
+		return 0;
+	}
+}