# Assuming your data is in a data frame named 'df'

library(dplyr)

​

df <- data.frame(

  trt = c("control", "early term", "late termination", "plant green"),

  mean = c(231, 214, 203, 176),

  sd = c(12.3, 14.6, 9.40, 28.5)

)

​

# Define character values corresponding to each treatment group

character_values <- c("A", "B", "C", "D")

​

# Adding a new column with character values

df <- df %>%

  mutate(Character_Column = character_values)

​

print(df)