useStream: Selects among available random streams.

In webb767/ppsmac: What the Package Does (One Line, Title Case)

Description

R's global environment variable .Random.seed is re-set so that random numbers generated after this call will follow from a designated random number state. This will fail unless the setSeeds function has already been called. This function simply selects the n'th random stream for use, presupposing that those stream states have already been set in the global environment.

Usage

useStream(n = NULL, origin = FALSE, verbose = FALSE)

Arguments

n	An integer that selects which random stream should be used for the following work.
origin	True or False. Should the stream be set at its original starting position, so as to re-generate the stream starting from the beginning? If FALSE, random numbers are drawn from the stream's current state.
verbose	Requests detailed output for diagnostics.

Details

This should handle three chores. 1) Copy the existing state of the random generator (.Random.seed) into currentStates[currentStream]. That allows us to "go back" to that generator when we want to. 2) Change currentStream variable to n, then 3) Re-set R's .Random.seed variable to the value from currentStates[currentStream], so that successively drawn random numbers follow the proper generator.

Value

Nothing. This function is run to change environment variables.

Author(s)

Paul E. Johnson [e-mail]

webb767/ppsmac documentation built on July 28, 2020, 12:59 a.m.