bind_cols()

This is an efficient implementation of the common pattern of do.call(rbind, dfs) or do.call(cbind, dfs) for binding many data frames into one (cited from tidyverse package site).

library(tidyverse)

## ── Attaching packages ─────────────────────────────────────────────────── tidyverse 1.2.1 ──

## ✔ ggplot2 3.1.0     ✔ purrr   0.2.5
## ✔ tibble  1.4.2     ✔ dplyr   0.7.7
## ✔ tidyr   0.8.2     ✔ stringr 1.3.1
## ✔ readr   1.1.1     ✔ forcats 0.3.0

## ── Conflicts ────────────────────────────────────────────────────── tidyverse_conflicts() ──
## ✖ dplyr::filter() masks stats::filter()
## ✖ dplyr::lag()    masks stats::lag()

one <- mtcars[,1:4]
two <- mtcars[,c(1:10)]
# Showing how dplyr::select in sapply works
sapply(list(ONE=one,TWO=two), dplyr::select,mpg) 

## $ONE.mpg
##  [1] 21.0 21.0 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 17.8 16.4 17.3 15.2
## [15] 10.4 10.4 14.7 32.4 30.4 33.9 21.5 15.5 15.2 13.3 19.2 27.3 26.0 30.4
## [29] 15.8 19.7 15.0 21.4
## 
## $TWO.mpg
##  [1] 21.0 21.0 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 17.8 16.4 17.3 15.2
## [15] 10.4 10.4 14.7 32.4 30.4 33.9 21.5 15.5 15.2 13.3 19.2 27.3 26.0 30.4
## [29] 15.8 19.7 15.0 21.4

# Convert into data.frame by bind_cols(). Bind_cols() can be used with list object.
sapply(list(ONE=one,TWO=two), dplyr::select,mpg) %>% bind_cols() 

## # A tibble: 32 x 2
##    ONE.mpg TWO.mpg
##      <dbl>   <dbl>
##  1    21      21  
##  2    21      21  
##  3    22.8    22.8
##  4    21.4    21.4
##  5    18.7    18.7
##  6    18.1    18.1
##  7    14.3    14.3
##  8    24.4    24.4
##  9    22.8    22.8
## 10    19.2    19.2
## # ... with 22 more rows

# does not work why?
sapply(list(ONE=one,TWO=two), dplyr::select,mpg) %>% bind_cols(one[,1],.) 

## Error in cbind_all(x): Argument 1 must have names

one[,1]

##  [1] 21.0 21.0 22.8 21.4 18.7 18.1 14.3 24.4 22.8 19.2 17.8 16.4 17.3 15.2
## [15] 10.4 10.4 14.7 32.4 30.4 33.9 21.5 15.5 15.2 13.3 19.2 27.3 26.0 30.4
## [29] 15.8 19.7 15.0 21.4

# Does work
sapply(list(ONE=one,TWO=two), dplyr::select,mpg) %>% bind_cols(list(model=rownames(mtcars)),.) 

## # A tibble: 32 x 3
##    model             ONE.mpg TWO.mpg
##    <chr>               <dbl>   <dbl>
##  1 Mazda RX4            21      21  
##  2 Mazda RX4 Wag        21      21  
##  3 Datsun 710           22.8    22.8
##  4 Hornet 4 Drive       21.4    21.4
##  5 Hornet Sportabout    18.7    18.7
##  6 Valiant              18.1    18.1
##  7 Duster 360           14.3    14.3
##  8 Merc 240D            24.4    24.4
##  9 Merc 230             22.8    22.8
## 10 Merc 280             19.2    19.2
## # ... with 22 more rows

enframe()

Another useful function is enframe¹.

x <- list( a = 1: 5, b = 3: 4, c = 5: 6 )
x

## $a
## [1] 1 2 3 4 5
## 
## $b
## [1] 3 4
## 
## $c
## [1] 5 6

df <- tibble::enframe( x) 
df

## # A tibble: 3 x 2
##   name  value    
##   <chr> <list>   
## 1 a     <int [5]>
## 2 b     <int [2]>
## 3 c     <int [2]>