Sets the behaviour of %dorng% foreach loops from a given version number.
doRNGversion(x)
NULL to
reset to the default behaviour, i.e. of the latest
version.a character string If x is missing this function
returns the version number from the current behaviour. If
x is specified, the function returns the old value
of the version number (invisible).
doRNGseed,
and therefore of %dorng% loops, changed in the
case where the current RNG was L'Ecuyer-CMRG. Using
set.seed before a non-seeded loop used not to be
identical to seeding via .options.RNG. Another bug
was that non-seeded loops would share most of their RNG
seed!
## Don't show:
# roxygen generated flag
options(R_CHECK_RUNNING_EXAMPLES_=TRUE)
## End Don't show
## Don't show:
registerDoSEQ()
## End Don't show
## Seeding when current RNG is L'Ecuyer-CMRG
RNGkind("L'Ecuyer")
doRNGversion("1.4")
# in version >= 1.4 seeding behaviour changed to fix a bug
set.seed(123)
res <- foreach(i=1:3) %dorng% runif(1)
res2 <- foreach(i=1:3) %dorng% runif(1)
stopifnot( !identical(attr(res, 'rng')[2:3], attr(res2, 'rng')[1:2]) )
res3 <- foreach(i=1:3, .options.RNG=123) %dorng% runif(1)
stopifnot( identical(res, res3) )
# buggy behaviour in version < 1.4
doRNGversion("1.3")
res <- foreach(i=1:3) %dorng% runif(1)
res2 <- foreach(i=1:3) %dorng% runif(1)
stopifnot( identical(attr(res, 'rng')[2:3], attr(res2, 'rng')[1:2]) )
res3 <- foreach(i=1:3, .options.RNG=123) %dorng% runif(1)
stopifnot( !identical(res, res3) )
# restore default RNG
RNGkind("default")
# restore to current doRNG version
doRNGversion(NULL)