| match.funfn {gsubfn} | R Documentation |
A generic match.fun.
match.funfn(x, ...) ## S3 method for class 'formula': match.funfn(x, ...) ## Default S3 method: match.funfn(x, ...)
x |
Function, character name of function or formula describing function. |
... |
Not used. |
The default method is the same as match.fun and the formula
method is the same as as.function.formula. This function can
be used within the body of a function to convert a function specification
whether its a function, character string or formula into an actual function.
Returns a function.
See Also match.fun,
as.function.formula.
# return first argument evaluated at second argument squared.
sq <- function(f, x) {
f <- match.funfn(f)
f(x^2)
}
# call sq using different forms for function
sq(function(x) exp(x)/x, pi)
f <- function(x) exp(x)/x
sq("f", pi)
sq(~ exp(x)/x, pi)
sq(x ~ exp(x)/x, pi)