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rand | Examples See Also |

Uniformly distributed random numbers and arrays

Y = rand(n) Y = rand(m,n) Y = rand([m n]) Y = rand(m,n,p,...) Y = rand([m n p...]) Y = rand(size(A)) rand s = rand('state')The

`rand`

function generates arrays of random numbers whose elements are uniformly distributed in the interval (`0`

,`1`

).
```
Y = rand(n)
```

returns an `n`

-by-`n`

matrix of random entries. An error message appears if `n`

is not a scalar.
```
Y = rand(m,n) or Y = rand([m n])
```

returns an `m`

-by-`n`

matrix of random entries.
```
Y = rand(m,n,p,...) or Y = rand([m n p...])
```

generates random arrays.
```
Y = rand(size(A))
```

returns an array of random entries that is the same size as `A`

.
`rand`

,

by itself, returns a scalar whose value changes each time it's referenced.
```
s = rand('state')
```

returns a 35-element vector containing the current state of the uniform generator. To change the state of the generator:`rand('seed',0)`

and` rand('seed',j)`

use the MATLAB 4 generator. `rand('seed') `

returns the current seed of the MATLAB 4 uniform generator. `rand('state',j)`

and `rand('state',s)`

use the MATLAB 5 generator.
`R`

`=`

`rand(3,4)`

may produce
R = 0.2190 0.6793 0.5194 0.0535 0.0470 0.9347 0.8310 0.5297 0.6789 0.3835 0.0346 0.6711This code makes a random choice between two equally probable alternatives.

if rand < .5 'heads' else 'tails' end

`randn`

` `

Normally distributed random numbers and arrays
`randperm`

` `

Random permutation

`sprand`

` `

Sparse uniformly distributed random matrix

`sprandn`

` `

Sparse normally distributed random matrix