merge_multiple_df: Merge One Data Frame Into Several Data Frames

In kthorstmann/padis: Functions For The Analysis Of Wake-Forest Data

Description

Merge One Data Frame Into Several Data Frames

Usage

merge_multiple_df(data_from, id_var, data_list_to, merge_down = TRUE,
  select_variables = NULL)

Arguments

data_from	The data frame from which to merge
id_var	The id or group-variable to merge by
data_list_to	A list of data frames into which the data frame data_from is merged into
merge_down	Logical, should the data_from be duplicated in order to merge down (TRUE), or should the duplicate rows be removed first in order to merge up? (FALSE). Default is to TRUE
select_vars	A character vector of the variables that should be selected from the data frame data_from. If NULL, all variables are selected and merged into the other data frames in data_list_to

Value

A list containing data frames with the same length as data_list_to.

Examples

## simulate data
# long data
data_long_1 <- data.frame(PAR.ID = letters[1:10],
                         var1 = sample(1:10, 10),
                         var2 = sample(1:10, 10))
data_long_2 <- data.frame(PAR.ID = sort(rep(letters[1:10], 3)),
                         var1 = sort(rep(1:10, 3)),
                         var2 = sort(rep(11:20, 3)))
data_long_2_er <- data.frame(PAR.ID = sort(rep(letters[1:10], 3)),
                         var1 = sort(rep(1:10, 3)),
                         var2 = sort(rep(11:20, 3)))
data_long_2_er[3, "var2"] <- 12 ## add a variable that is not the same as the other variables
data_long_3 <- data.frame(PAR.ID = rep(letters[1:10], 4),
                         var1 = sample(1:40, 40),
                         var2 = sample(1:40, 40))
# short data
data_short_2 <- data.frame(PAR.ID = rep(letters[1:10], 1),
                          var1 = sample(1:40, 10),
                          var2 = sample(1:40, 10))
data_short_3 <- data.frame(PAR.ID = rep(letters[1:10], 1),
                          var1 = sample(1:40, 10),
                          var2 = sample(1:40, 10))
## merge down, i. e. duplicate rows when going from a higher data set (e.g .level-2) to a lower data set (e.g. level-1)
merge_multiple_df(data_long_1, id_var="PAR.ID", list(data_long_2, data_long_3), merge_down = TRUE)

## merge up, i. e. make the longer data frame short first and merge then
merge_multiple_df(data_from = data_long_2, id_var="PAR.ID", data_list_to = list(data_short_2, data_short_3), merge_down = FALSE)
## merge up, i. e. make the longer data frame short first and merge then and give a warning if duplicates arise
merge_multiple_df(data_from = data_long_2_er, id_var="PAR.ID", data_list_to = list(data_short_2, data_short_3), merge_down = FALSE)

kthorstmann/padis documentation built on May 24, 2019, 5:01 a.m.