How to convert a factor to integer\numeric without loss of information in R?

When you directly use as.numeric() on a factor, you get the underlying integer codes rather than the readable labels. To convert a factor to numeric or integer without losing the actual category labels, first convert to character and then to numeric. For example:

# Suppose 'f' is a factor
f <- factor(c("apple","banana","apple"))
# Correct way to get numeric representation of labels
num_vals <- as.numeric(as.character(f)) 

This way, if f has labels like "apple" and "banana", you’ll see meaningful numeric values derived from the labels, not just internal codes. If you only need an integer representation, you can wrap it with as.integer(as.character(f)).

It’s always good to validate that you really want the textual labels turned into numbers, especially if you’re applying calculations like mean or sum. Sometimes you might just want to keep them as distinct categories.

Next Steps

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