Replace NAs with mean of the same column of a data.table

Question

I want to replace NAs present in a column of a DATA TABLE with the mean of the same column. I am doing the following. But it is not working.

ww <- data.ta         


        

Answer 1

In base R:

ww$Sepal.Length[is.na(ww$Sepal.Length)] <- mean(ww$Sepal.Length, na.rm = T)