Random sample

`y = randsample(n,k)`

y = randsample(population,k)

y = randsample(n,k,replacement)

y
= randsample(population,k,replacement)

y = randsample(n,k,true,w)

y
= randsample(population,k,true,w)

y = randsample(s,...)

`y = randsample(n,k)`

returns a `k`

-by-`1`

vector `y`

of
values sampled uniformly at random, without replacement, from the
integers 1 to `n`

.

`y = randsample(population,k)`

returns a
vector of `k`

values sampled uniformly at random,
without replacement, from the values in the vector `population`

.
The orientation of `y`

(row or column) is the same
as `population`

.

`y = randsample(n,k,replacement)`

or ```
y
= randsample(population,k,replacement)
```

returns a sample
taken with replacement if `replacement`

is `true`

,
or without replacement if `replacement`

is `false`

.
The default is `false`

.

`y = randsample(n,k,true,w)`

or ```
y
= randsample(population,k,true,w)
```

returns a weighted sample
taken with replacement, using a vector of positive weights `w`

,
whose length is `n`

. The probability that the integer `i`

is
selected for an entry of `y`

is `w(i)/sum(w)`

.
Usually, `w`

is a vector of probabilities. `randsample`

does
not support weighted sampling without replacement.

`y = randsample(s,...)`

uses the stream `s`

for
random number generation. `s`

is a member of the `RandStream`

class. Default is the MATLAB^{®} default
random number stream.

Draw a single value from the integers `1`

through `10`

:

n = 10; x = randsample(n,1);

Draw a single value from the population `1`

through `n`

,
where `n > 1`

:

y = randsample(1:n,1);

y = population(randsample(length(population),k)) instead of |

Generate a random sequence of the characters `A`

, `C`

, `G`

,
and `T`

, with replacement, according to the specified
probabilities.

R = randsample('ACGT',48,true,[0.15 0.35 0.35 0.15])

`datasample`

| `rand`

| `randperm`

| `RandStream`

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