no <- c(10, 20, 30)
age <- c(18, 21, 20)
gender <- c('F', 'M', 'F')
students <- data.frame(no, age, gender)
# here type conversion occurs
students['4', ] <- c(40, 20, 'F')
str(students)
result is like $ age: chr "18" "21" ...
why data type changes and how I prevent it?
what I tried: googling for 10 minutes and got nothing