Merge list of data.frames

merge_list.R

# packages
library("dplyr")
library("reshape")
library("microbenchmark")

set.seed(1)

# prep data
m <- mtcars
n <- 50L # number of data.frames
x <- replicate(n, within(setNames(m[sample(1:nrow(m), 25, FALSE),], paste0(names(m), sample(1:5, 1))), car <- sample(1:1000, 25)), simplify = FALSE)

# check structures
reduce_base <- Reduce(function(...) merge(..., by = "car", all = TRUE), x)
str(reduce_base)
reshape <- reshape::merge_all(x, by = "car", all.x = TRUE, all.y = TRUE)
str(reshape) # structure doesn't match
reduce_dplyr <- Reduce(function(...) dplyr::full_join(..., by = "car"), x)
str(reduce_dplyr)

microbenchmark(
               Reduce(function(...) merge(..., by = "car", all=TRUE), x), 
               #reshape::merge_all(x, all.x = TRUE, all.y = TRUE),
               Reduce(function(...) full_join(..., by = "car"), x)
               )
## Unit: milliseconds
##                                                         expr       min        lq      mean    median        uq       max neval cld
##  Reduce(function(...) merge(..., by = "car", all = TRUE), x) 1148.0797 1238.2552 1397.2183 1291.3522 1390.4031 2950.8649   100   b
##          Reduce(function(...) full_join(..., by = "car"), x)  114.2629  130.7524  169.3708  167.5244  184.5012  367.1367   100  a