How do I replace NA values with zeros in an R dataframe?

Question

I have a data frame and some columns have NA values.

How do I replace these NA values with zeroes?

Answer 1

For a single vector:

x <- c(1,2,NA,4,5)
x[is.na(x)] <- 0

For a data.frame, make a function out of the above, then apply it to the columns.

Please provide a reproducible example next time as detailed here:

How to make a great R reproducible example?