lapplI {labelmachine}

Improve lapply and sapply with index

Description

Improve base::lapply() and base::sapply() functions by allowing an extra index argument .I to be passed into the function given in FUN. If the function given in FUN has an argument .I then, for each entry of X passed into FUN the corresponding index is passed into argument .I. If the function given in FUN has no argument .I, then lapplI and sapplI are exactly the same as base::lapply() and base::sapply(). Besides this extra feature, there is no difference to base::lapply() and base::sapply().

Usage

lapplI(X, FUN, ...)

sapplI(X, FUN, ..., simplify = TRUE, USE.NAMES = TRUE)

Arguments

X

a vector (atomic or list) or an expression object. Other objects (including classed objects) will be coerced by base::as.list.

FUN

Here comes the great difference to base::lapply() and base::sapply(). When using lapplI and sapplI, the function passed into FUN may also have an extra argument .I. If it does, then for each item of X the current item index is passed into argument .I of FUN. Besides this extra feature, there is no difference to base::lapply() and base::sapply().

...

optional arguments to FUN.

simplify

logical or character string; should the result be simplified to a vector, matrix or higher dimensional array if possible? For sapply it must be named and not abbreviated. The default value, TRUE, returns a vector or matrix if appropriate, whereas if simplify = "array" the result may be an array of “rank” (=length(dim(.))) one higher than the result of FUN(X[[i]]).

USE.NAMES

logical; if TRUE and if X is character, use X as names for the result unless it had names already. Since this argument follows ... its name cannot be abbreviated.