The function accepts a numeric vector and maps each integer to its positional
representation in a base-26 derived system. This mapping follows standard
spreadsheet conventions where the sequence progresses from "A" through "Z",
followed by "AA", "AB", and so forth.
Validation is performed to ensure the input is numeric and finite. In accordance
with the Office Open XML specification used by most spreadsheet software, the
maximum supported column index is 16,384, which corresponds to the column
label "XFD". Inputs exceeding this range may result in coordinates that are
incompatible with standard spreadsheet applications.