diff options
Diffstat (limited to 'lib/libc/gen/rand48.3')
| -rw-r--r-- | lib/libc/gen/rand48.3 | 9 |
1 files changed, 6 insertions, 3 deletions
diff --git a/lib/libc/gen/rand48.3 b/lib/libc/gen/rand48.3 index 86e7a2f..ac7e33e 100644 --- a/lib/libc/gen/rand48.3 +++ b/lib/libc/gen/rand48.3 @@ -50,7 +50,8 @@ The .Fn rand48 family of functions generates pseudo-random numbers using a linear -congruential algorithm working on integers 48 bits in size. The +congruential algorithm working on integers 48 bits in size. +The particular formula employed is r(n+1) = (a * r(n) + c) mod m where the default values are @@ -64,7 +65,8 @@ computational step is to perform a single iteration of the algorithm. .Fn drand48 and .Fn erand48 -return values of type double. The full 48 bits of r(n+1) are +return values of type double. +The full 48 bits of r(n+1) are loaded into the mantissa of the returned value, with the exponent set such that the values produced lie in the interval [0.0, 1.0). .Pp @@ -119,7 +121,8 @@ also initializes the internal buffer r(n) of and .Fn mrand48 , but here all 48 bits of the seed can be specified in an array of 3 shorts, -where the zeroth member specifies the lowest bits. Again, +where the zeroth member specifies the lowest bits. +Again, the constant multiplicand and addend of the algorithm are reset to the default values given above. .Fn seed48 |
