Prepare a vector argument — prep_vector

This is a helper function for many *_byname functions.

Usage

prep_vector_arg(a, vector_arg)

Arguments

a: A matrix or list of matrices.
vector_arg: The vector argument over which to apply a calculation.

Value

vector_arg, possibly modified when a is a list.

Details

It is potentially ambiguous to specify a vector or matrix argument, say, margin = c(1, 2) when applying the *_byname functions to unary list of a. Rather, one should specify, say, margin = list(c(1, 2)) to avoid ambiguity. If a is a list, vector_arg is not a list and has length > 1 and length not equal to the length of a, this function returns a list value for vector_arg. If a is not a list and vector_arg is a list, this function returns an un-recursive, unlisted version of vector_arg.

Note that if vector_arg is a single matrix, it is automatically enclosed by a list when a is a list.

Examples

m <- matrix(c(2, 2))
prep_vector_arg(m, vector_arg = c(1,2))
#> [1] 1 2
prep_vector_arg(list(m), vector_arg = c(1,2))
#> [[1]]
#> [1] 1 2
#> 
prep_vector_arg(list(m, m), vector_arg = c(1,2))
#> [1] 1 2
prep_vector_arg(list(m, m, m), vector_arg = c(1,2))
#> [[1]]
#> [1] 1 2
#>