r rename column if code example

Example 1: r rename column based on variable

# Rename column by name: change "beta" to "two"
names(d)[names(d)=="beta"] <- "two"
d
#>   alpha two gamma
#> 1     1   4     7
#> 2     2   5     8
#> 3     3   6     9

# You can also rename by position, but this is a bit dangerous if your data
# can change in the future. If there is a change in the number or positions of
# columns, then this can result in wrong data.

# Rename by index in names vector: change third item, "gamma", to "three"
names(d)[3] <- "three"
d
#>   alpha two three
#> 1     1   4     7
#> 2     2   5     8
#> 3     3   6     9

Example 2: r rename column based on variable

df %>% rename(!!variable := name_of_col_from_df)

Example 3: r rename column based on variable

names(d) <- sub("^alpha$", "one", names(d))
d
#>   one two three
#> 1   1   4     7
#> 2   2   5     8
#> 3   3   6     9

# Across all columns, replace all instances of "t" with "X"
names(d) <- gsub("t", "X", names(d))
d
#>   one Xwo Xhree
#> 1   1   4     7
#> 2   2   5     8
#> 3   3   6     9

# gsub() replaces all instances of the pattern in each column name.
# sub() replaces only the first instance in each column name.