cbind a dynamic column name from a string in R

Question

I want to cbind a column to the data frame with the column name dynamically assigned from a string

y_attribute = \"Survived\"
cbind(test_data, y_attribute =         


        

Answer 1

Not proud of this but I usually will do somethingl like this:

dyn.col <- "XYZ"
cbind(test.data, UNIQUE_NAMEXXX=NA)
colnames(test.data)[colnames(test.data == 'UNIQUE_NAMEXXX')] <- dyn.col

Answer 2

You don't actually need cbind to add a new column. Any of these will work:

test_data[, y_attribute] = NA # data frame row,column syntax
test_data[y_attribute] = NA   # list syntax (would work for multiple columns at once)
test_data[[y_attribute]] = NA # list single item syntax (single column only)

New columns are added after the existing columns, just like cbind.

Answer 3

We can use tidyverse to do this

library(dplyr)
test_data %>%
     mutate(!! y_attribute := NA)
#   col1 Survived
#1    1       NA
#2    2       NA
#3    3       NA
#4    4       NA
#5    5       NA

data

test_data <- data.frame(col1 = 1:5)

Answer 4

We can also do it with data.table

library(data.table)
setDT(test_data)[, (y_attribute) := NA]