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-rw-r--r--src/prng/drand48.c19
1 files changed, 19 insertions, 0 deletions
diff --git a/src/prng/drand48.c b/src/prng/drand48.c
new file mode 100644
index 00000000..d808353c
--- /dev/null
+++ b/src/prng/drand48.c
@@ -0,0 +1,19 @@
+#include <stdlib.h>
+#include <inttypes.h>
+
+uint64_t __rand48_step(unsigned short *xi, unsigned short *lc);
+extern unsigned short __seed48[7];
+
+double erand48(unsigned short s[3])
+{
+ union {
+ uint64_t u;
+ double f;
+ } x = { 0x3ff0000000000000ULL | __rand48_step(s, __seed48+3)<<4 };
+ return x.f - 1.0;
+}
+
+double drand48(void)
+{
+ return erand48(__seed48);
+}