matlab 中抽取随机数的函数

Question

如题所述

Answer 1

设取值区间为[a,b]，则要在此区间选取一个随机数，程序为：

a=rand()*(b-a)+a

若要求随机数是整数，则程序为：

a=ceil(rand()*(b-a))+a

这样即可！！！

Answer 2

help rand

RAND Uniformly distributed random numbers.
RAND(N) is an N-by-N matrix with random entries, chosen from
a uniform distribution on the interval (0.0,1.0).
RAND(M,N) and RAND([M,N]) are M-by-N matrices with random entries.
RAND(M,N,P,...) or RAND([M,N,P,...]) generate random arrays.
RAND with no arguments is a scalar whose value changes each time it
is referenced. RAND(SIZE(A)) is the same size as A.

RAND produces pseudo-random numbers. The sequence of numbers
generated is determined by the state of the generator. Since MATLAB
resets the state at start-up, the sequence of numbers generated will
be the same unless the state is changed.

S = RAND('state') is a 35-element vector containing the current state
of the uniform generator. RAND('state',S) resets the state to S.
RAND('state',0) resets the generator to its initial state.
RAND('state',J), for integer J, resets the generator to its J-th state.
RAND('state',sum(100*clock)) resets it to a different state each time.

This generator can generate all the floating point numbers in the
closed interval [2^(-53), 1-2^(-53)]. Theoretically, it can generate
over 2^1492 values before repeating itself.

MATLAB Version 4.x used random number generators with a single seed.
RAND('seed',0) and RAND('seed',J) cause the MATLAB 4 generator to be used.
RAND('seed') returns the current seed of the MATLAB 4 uniform generator.
RAND('state',J) and RAND('state',S) cause the MATLAB 5 generator to be used.

See also RANDN, SPRAND, SPRANDN, RANDPERM.