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A random state object represents the state of the random number generator. The state comprises 627 32-bit words.
make_random_state (n)
returns a new random state object
created from an integer seed value equal to n modulo 2^32.
n may be negative.
make_random_state (s)
returns a copy of the random state s.
make_random_state (true)
returns a new random state object,
using the current computer clock time as the seed.
make_random_state (false)
returns a copy of the current state
of the random number generator.
Copies s to the random number generator state.
set_random_state
always returns done
.
Returns a pseudorandom number. If x is an integer,
random (x)
returns an integer from 0 through x - 1
inclusive. If x is a floating point number, random (x)
returns a nonnegative floating point number less than x. random
complains with an error if x is neither an integer nor a float, or if
x is not positive.
The functions make_random_state
and set_random_state
maintain the state of the random number generator.
The Maxima random number generator is an implementation of the Mersenne twister MT 19937.
Examples:
(%i1) s1: make_random_state (654321)$
(%i2) set_random_state (s1); (%o2) done
(%i3) random (1000); (%o3) 768
(%i4) random (9573684); (%o4) 7657880
(%i5) random (2^75); (%o5) 11804491615036831636390
(%i6) s2: make_random_state (false)$
(%i7) random (1.0); (%o7) 0.2310127244107132
(%i8) random (10.0); (%o8) 4.394553645870825
(%i9) random (100.0); (%o9) 32.28666704056853
(%i10) set_random_state (s2); (%o10) done
(%i11) random (1.0); (%o11) 0.2310127244107132
(%i12) random (10.0); (%o12) 4.394553645870825
(%i13) random (100.0); (%o13) 32.28666704056853
Previous: Trigonometric Functions, Up: Mathematical Functions [Contents][Index]