R: Random seed

with_seed {withr} | R Documentation

## Random seed

### Description

`with_seed()` runs code with a specific random seed and resets it afterwards.

`with_preserve_seed()` runs code with the current random seed and resets it afterwards.

### Usage

    with_seed(seed, code)

    with_preserve_seed(code)

### Arguments

`seed` | `[integer(1)]` The random seed to use to evaluate the code.
`code` | `[any]` Code to execute in the temporary environment

### Value

`[any]`
The results of the evaluation of the `code` argument.

### See Also

`withr` for examples

### Examples

    # Same random values:
    with_preserve_seed(runif(5))
    with_preserve_seed(runif(5))

    # Use a pseudorandom value as seed to advance the RNG and pick a different
    # value for the next call:
    with_seed(seed <- sample.int(.Machine$integer.max, 1L), runif(5))
    with_seed(seed, runif(5))
    with_seed(seed <- sample.int(.Machine$integer.max, 1L), runif(5))

[Package withr version 2.1.2 Index]