withr (version 2.4.2)

with_seed: 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,
  .rng_kind = "default",
  .rng_normal_kind = "default",
  .rng_sample_kind = "default"
)
local_seed(
  seed,
  .local_envir = parent.frame(),
  .rng_kind = "default",
  .rng_normal_kind = "default",
  .rng_sample_kind = "default"
)
with_preserve_seed(code)
local_preserve_seed(.local_envir = parent.frame())

Arguments

seed

[integer(1)] The random seed to use to evaluate the code.

code

[any] Code to execute in the temporary environment

.rng_kind

[character(1)] Kind of (uniform) RNG to use.

.rng_normal_kind

[character(1)] Kind of normal RNG to use.

.rng_sample_kind

[character(1)] Kind of RNG to use for sampling.

.local_envir

[environment] The environment to use for scoping.

Value

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

See Also

withr for examples

Examples

# NOT RUN {
# 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))
# }