r rename columns

library(plyr)
rename(d, c("beta"="two", "gamma"="three"))
#>   alpha two three
#> 1     1   4     7
#> 2     2   5     8
#> 3     3   6     9

colnames(trSamp)[2] <- "newname2"

# df = dataframe
# old.var.name = The name you don't like anymore
# new.var.name = The name you want to get

names(df)[names(df) == 'old.var.name'] <- 'new.var.name'

df <- rename(df, new_name = old_name) #For renaming dataframe column
 
tbl <- rename(tbl, new_name = old_name) #For renaming tibble column
 
tbl <- tbl %>% rename(new_name = old_name) #For renaming tibble column using dplyrpipe 
                                           #operator 

colnames(df)[which(names(df) == "columnName")] <- "newColumnName"