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These functions transform your variable by reference, with no copies being made. It is advisable to only use these if you know what you are doing.
set_abs(x)set_floor(x)
set_ceiling(x)
set_trunc(x)
set_exp(x)
set_sqrt(x)
set_change_sign(x)
set_round(x, digits = 0)
set_log(x, base = exp(1))
set_pow(x, y)
set_add(x, y)
set_subtract(x, y)
set_multiply(x, y)
set_divide(x, y)
The exact same object with no copy made, just transformed.
A numeric vector.
Number of digits to round to.
Logarithm base.
A numeric vector.
These functions are particularly useful for situations
where you have made a copy and then
wish to perform further operations without creating more copies.
NA and NaN values are ignored though in some instances NaN values may
be replaced with NA.
These functions will not work on any classed objects, meaning they
only work on standard integer and numeric vectors and matrices.
A copy is only made in certain instances, e.g. when passing an integer vector
to set_log(). A warning will always be thrown in this instance alerting the user
to assign the output to an object because x has not been updated by reference.
To ensure consistent and expected outputs, always assign the output to the same object,
e.g.
x <- set_log(x) (do this)
set_log(x) (don't do this)
x2 <- set_log(x) (Don't do this either)
No copy is made here unless x is an integer vector.
library(cheapr)
library(bench)
x <- rnorm(2e05)
options(cheapr.cores = 2)
mark(
base = exp(log(abs(x))),
cheapr = set_exp(set_log(set_abs(x)))
)
options(cheapr.cores = 1)
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