joyn (version 0.2.4)

check_by_vars: Check by input

Description

This function checks the variable name(s) to be used as key(s) of the join

Usage

check_by_vars(by, x, y)

Value

list with information about by variables

Arguments

by

A vector of shared column names in x and y to merge on. This defaults to the shared key columns between the two tables. If y has no key columns, this defaults to the key of x.

x, y

data tables. y is coerced to a data.table if it isn't one already.

Examples

if (FALSE) {
x1 = data.frame(
       id = c(1L, 1L, 2L, 3L, NA_integer_),
       t  = c(1L, 2L, 1L, 2L, NA_integer_),
       x  = 11:15)
y1 = data.frame(id = 1:2,
                y  = c(11L, 15L))
# With var "id" shared in x and y
joyn:::check_by_vars(by = "id", x = x1, y = y1)
}