| Vectorize {base} | R Documentation |
Vectorize creates a function wrapper that vectorizes the
action of its argument FUN.
Vectorize(FUN, vectorize.args = arg.names, SIMPLIFY = TRUE,
USE.NAMES = TRUE)
FUN |
function to apply, found via |
vectorize.args |
a character vector of arguments which should be
vectorized. Defaults to all arguments of |
SIMPLIFY |
logical or character string; attempt to reduce the
result to a vector, matrix or higher dimensional array; see
the |
USE.NAMES |
logical; use names if the first ... argument has names, or if it is a character vector, use that character vector as the names. |
The arguments named in the vectorize.args argument to
Vectorize are the arguments passed in the ... list to
mapply. Only those that are actually passed will be
vectorized; default values will not. See the examples.
Vectorize cannot be used with primitive functions as they do
not have a value for formals.
A function with the same arguments as FUN, wrapping a call to
mapply.
# We use rep.int as rep is primitive
vrep <- Vectorize(rep.int)
vrep(1:4, 4:1)
vrep(times = 1:4, x = 4:1)
vrep <- Vectorize(rep.int, "times")
vrep(times = 1:4, x = 42)
f <- function(x = 1:3, y) c(x,y)
vf <- Vectorize(f, SIMPLIFY = FALSE)
f(1:3, 1:3)
vf(1:3, 1:3)
vf(y = 1:3) # Only vectorizes y, not x
# Nonlinear regression contour plot, based on nls() example
require(graphics)
SS <- function(Vm, K, resp, conc) {
pred <- (Vm * conc)/(K + conc)
sum((resp - pred)^2 / pred)
}
vSS <- Vectorize(SS, c("Vm", "K"))
Treated <- subset(Puromycin, state == "treated")
Vm <- seq(140, 310, length.out = 50)
K <- seq(0, 0.15, length.out = 40)
SSvals <- outer(Vm, K, vSS, Treated$rate, Treated$conc)
contour(Vm, K, SSvals, levels = (1:10)^2, xlab = "Vm", ylab = "K")