rand

Arguments

mi

integers

key

character string with value in "uniform", "normal"

x

a matrix. Only its dimensions are taken into account.

Description

random matrix generator.

Warning: without a seed, the sequence will remain the same from a session to the other.

At the beginning of each script using rand function, you should use:

rand('seed',getdate('s'))

Without key argument the syntaxes below produce random matrices with the current random generator (default is "uniform")

rand(m1,m2)

is a random matrix of dimension m1 by m2.

rand(m1,m2,..,mn)

is a random matrix of dimension m1 by m2,.. by mn.

rand(a)

is a random matrix of same size as a. rand(a) is complex if a is a complex matrix.

rand() : with no arguments gives a scalar whose value changes

each time it is referenced.

If present, the key argument allows to specifie an other random distribution.

rand('uniform')

The current random generator is set to a uniform random generator. Random numbers are uniformly distributed in the interval (0,1).

rand('normal')

The current random generator is set to a Gaussian (with mean 0 and variance 1) random number generator.

str=rand('info')

return the type of the default random generator ('uniform' or 'normal')

IT is possible to (re-)initialize the seed of the rand generator:

rand('seed')

returns the current value of the seed.

rand('seed',n)

puts the seed to n. (by default n=0 at first call).

Remark

Use the more powerful function grand instead.

Examples

x=rand(10,10,'uniform')
rand('normal')
rand('info')
y=rand(x,'normal');
x=rand(2,2,2)

See Also

• grand — Random number generator(s)
• ssrand — random system generator