/*****************************************************************************
- * nrand48.c: POSIX nrand48() replacement
+ * nrand48.c: POSIX erand48(), jrand48() and nrand48() replacements
*****************************************************************************
* Copyright © 2010 Rémi Denis-Courmont
*
#include <inttypes.h>
-long nrand48 (unsigned short subi[3])
+static uint64_t iterate48 (unsigned short subi[3])
{
- const uint64_t a = UINT64_C(0x5DEECE66D16);
+ const uint64_t a = UINT64_C(0x5DEECE66D);
const unsigned c = 13;
const uint64_t mask = UINT64_C(0xFFFFFFFFFFFF); // 48 bits
subi[1] = (x >> 16) & 0xFFFF;
subi[2] = (x >> 0) & 0XFFFF;
- return x >> 16;
+ return x;
+}
+
+double erand48 (unsigned short subi[3])
+{
+ uint64_t r = iterate48 (subi);
+ return ((double)r) / 281474976710655.;
+}
+
+long jrand48 (unsigned short subi[3])
+{
+ return ((int64_t)iterate48 (subi)) >> 16;
+}
+
+long nrand48 (unsigned short subi[3])
+{
+ return iterate48 (subi) >> 17;
}