char.expand {base} | R Documentation |
Seeks a unique match of its first argument among the elements of its second. If successful, it returns this element; otherwise, it performs an action specified by the third argument.
char.expand(input, target, nomatch = stop("no match"))
input |
a character string to be expanded. |
target |
a character vector with the values to be matched against. |
nomatch |
an R expression to be evaluated in case expansion was not possible. |
This function is particularly useful when abbreviations are allowed in function arguments, and need to be uniquely expanded with respect to a target table of possible values.
A length-one character vector, one of the elements of target
(unless nomatch
is changed to be a non-error, when it can be a
zero-length character string).
charmatch
and pmatch
for performing
partial string matching.
locPars <- c("mean", "median", "mode") char.expand("me", locPars, warning("Could not expand!")) char.expand("mo", locPars)