How to add new column with variable using mutate

Question

How to add new column with variable? I have a problem must use variable to add column.

library(dplyr)

data(iris)

x<-"newcol"

iris %>% mutate(x="only test") %>% head()

After running the above code, the new added column's name is x, not expect newcol. how to fix it?

Answer 1

library(dplyr)
#> 
#> Attaching package: 'dplyr'
#> The following objects are masked from 'package:stats':
#> 
#>     filter, lag
#> The following objects are masked from 'package:base':
#> 
#>     intersect, setdiff, setequal, union

iris %>% 
  mutate(newcol = "test") %>% 
  head()
#>   Sepal.Length Sepal.Width Petal.Length Petal.Width Species newcol
#> 1          5.1         3.5          1.4         0.2  setosa   test
#> 2          4.9         3.0          1.4         0.2  setosa   test
#> 3          4.7         3.2          1.3         0.2  setosa   test
#> 4          4.6         3.1          1.5         0.2  setosa   test
#> 5          5.0         3.6          1.4         0.2  setosa   test
#> 6          5.4         3.9          1.7         0.4  setosa   test

^{Created on 2022-05-06 by the reprex package (v2.0.1)}