How to avoid NA columns in dcast() output?

Question

How can I avoid NA columns in dcast() output from the reshape2 package?

In this dummy example the dcast() o

Answer 1

Here is how I was able to get around it:

iris[is.na(iris)] <- 'None'

x <- dcast(iris, Species ~ Species2, value.var="Sepal.Width", fun.aggregate = length)

x$None <- NULL

The idea is that you replace all the NAs with 'None', so that dcast creates a column called 'None' rather than 'NA'. Then, you can just delete that column in the next step if you don't need it.