7.3.8 Producing random matrices: randmatrix ranm randMat
You can produce a random vector or matrix with the randmatrix
(or ranm or randMat) command. (See also sections
5.27.25 and 5.44.3.) The randmatrix command
has the following possible arguments.

An integer n

With an integer n, randmatrix(n) will return a vector of
length n whose elements are integers chosen randomly from
[−99,−98,…,98,99] with equal probability. If you enter
randmatrix(5)
you might get
[86,97,82,7,27]
 Two integers n and p

Given two integers n and p, randmatrix(n,p) will
return an n× p matrix whose elements are integers chosen randomly from
[−99,99] with equal probability. If you enter
randmatrix(2,3)
you might get
[[26,89,63],[49,86,64]]
 Three integers n, p and a

Given three integers n, p and a, randmatrix(n,p,a) will
return an n× p matrix whose elements are integers chosen randomly from
[0,a) (or (a,0] is a is negative) with equal probability. If you enter
randmatrix(2,3,10)
you might get
[[4,7,6],[7,4,5]]
 Two integers n and p, and an interval a..b.

Given two integers n, p and an a..b,
randmatrix(n,p,a..b) will
return an n× p matrix whose elements are real numbers chosen randomly from
[a,b) with equal probability. If you enter
randmatrix(2,3,0..1)
you might get
[[0.90923402831,0.594602484722,0.250897713937],[0.332611694932,0.145975249354,0.543010003399]]
 Two integers n and p and a function (which must be quoted)
to produce random numbers

In this case, the third argument must be
one of ’rand(n)’, ’binomial(n,p)’,
’binomial,n,p’, ’randbinomial(n,p)’,
’multinomial(P,K)’, ’multinomial,P,K’,
’randmultinomial(P,K)’, ’poisson(λ)’,
’poisson, λ’, ’randpoisson(λ)’,
’normald(µ,σ)’, ’normald,µ,σ’,
’randnorm(µ,σ)’, ’exp(a)’,
’exp,a’, ’randexp(a)’,
’fisher(n,m)’, ’fisher,n,m’, or
’randfisher(n,m)’.
Given such an R, the command randmatrix(n,p,R) will
return an n× p matrix whose elements are numbers chosen
randomly according to the rule determined by R.
If you enter
randmatrix(2,3,’randnorm(2,1)’)
you might get
[[2.6324726358,0.539273367446,0.793750476229],[2.24729803442,1.28189228187,2.25750809791]]