listr (version 0.1.0)

list_join_df: Join a list of data frames on a common index.

Description

Join a list of data frames on a common index.

Usage

list_join_df(in_list, join_type = "inner", by = NULL, skip_non_df = FALSE)

Value

A data frame.

Arguments

in_list

A list of data frames.

join_type

A string specifying the join strategy to use. Must be one of "inner", "left", "right" or "full".

by

Optional vector of strings specifying columns to merge by.

skip_non_df

Should elements that are not data.frames be skipped?

Details

Using `join_type` you can specify how to join the data. The default `inner` will keep only observations present in all data frames. `left` will keep all observations from the first data frame in the list and merge the matching items from the rest, while `right` will keep all observations from the last data frame in the list. Using `full` will keep all observations.

If `by` is not supplied, then data frames will be merged on columns with names they all have. Otherwise merging is done on the specified columns.

Using `skip_non_df` you can specify to omit elements from the input list that are not data frames. If FALSE (the default) an error will be thrown if elements are present that are not data frames.

Examples

dfl <- list(data.frame(idx = sample(100, 30), x = rnorm(30)),
            data.frame(idx = sample(100, 30), y = rnorm(30)),
            data.frame(idx = sample(100, 30), z = rnorm(30)))
list_join_df(dfl)