kim (version 0.5.3)

merge_data_table_list: Merge a list of data tables

Description

Successively merge a list of data.table objects in a recursive fashion. That is, merge the (second data table in the list) around the first data table in the list; then, around this resulting data table, merge the third data table in the list; and so on.

Usage

merge_data_table_list(dt_list = NULL, id = NULL, silent = TRUE)

Value

a data.table object, which successively merges (joins) a data table around (i.e., outside) the previous data table in the list of data tables.

Arguments

dt_list

a list of data.table objects

id

name of the column that will contain the ID values in the data tables. The name of the ID column must be identical in the all data tables.

silent

If silent = TRUE, no message will be printed regarding how many ID values and column names were duplicated. If silent = FALSE, messages will be printed regarding how many ID values and column names were duplicated. (default = FALSE)

Details

If there are any duplicated ID values and column names across the data tables, the cell values in the earlier data table will remain intact and the cell values in the later data table will be discarded for the resulting merged data table in each recursion.

Examples

data_1 <- data.table::data.table(
id_col = c(4, 2, 1, 3),
a = 3:6,
b = 5:8,
c = c("w", "x", "y", "z"))
data_2 <- data.table::data.table(
id_col = c(1, 4, 99),
d = 6:8,
b = c("p", "q", "r"),
e = c(TRUE, FALSE, FALSE))
data_3 <- data.table::data.table(
id_col = c(200, 3),
f = 11:12,
b = c(300, "abc"))
merge_data_table_list(
dt_list = list(data_1, data_2, data_3), id = "id_col")