R: fill down multiple columns

We can use fill_ when we select variables with names.

library(tidyr)# using tidyr_0.4.1.9000res <- fill_(df, names(df))head(res)#   col1 col2 col3#1    1   NA    b#2    1    3    b#3    2    4    a#4    2    4    a#5    2    1    a#6    3    4    a

Other option would be

fill(df, everything())

However, if we use fill with names(df)), it will give the same error as the OP showed

fill(df, names(df)[1])#Error: All select() inputs must resolve to integer column positions.#The following do not:#*  names(df)[1]

data

set.seed(24) df <- data.frame(col1= sample(c(NA, 1:3), 20, replace=TRUE),                   col2 = sample(c(NA, 1:5), 20, replace=TRUE),                  col3 = sample(c(NA, letters[1:5]), 20, replace=TRUE),                  stringsAsFactors=FALSE)

Another alternative with package zoo which can also fill backwards if desired.On the sample created above-

zoo::na.locf(df)   col1 col2 col31     2    4    e2     2    4    e3     3    4    a4     2    4    b5     1    3    d6     2    4    d7     2    1    b8     1    1    e9     3    3    e10    1    2    e11    1    4    e12    1    1    e13    3    1    a14    3    4    c15    3    3    b16    2    3    e17    3    1    e18    3    2    b19    3    5    c20    3    5    e

where df is

   col1 col2 col31     2    4    e2     2   NA    e3     3    4    a4     2    4    b5     1    3    d6     2    4 <NA>7    NA    1    b8     1   NA    e9     3    3 <NA>10    1    2    e11    1    4    e12   NA    1 <NA>13    3   NA    a14   NA    4    c15    3    3    b16    2    3    e17    3    1    e18   NA    2    b19   NA    5    c20    3    5    e

Building off @akrun's comment and data, here are two other ways using the tidyr:

Data

set.seed(24)df <- data.frame(col1= sample(c(NA, 1:3), 20, replace=TRUE),                  col2 = sample(c(NA, 1:5), 20, replace=TRUE),                 col3 = sample(c(NA, letters[1:5]), 20, replace=TRUE),                 stringsAsFactors=FALSE)

Two Options

#Specify column namesfill(df, c("col1", "col2"), .direction = "down")#Specify range of columnsfill(df, c(col1:col3), .direction = "down")