by David Lillis, Ph.D.

One data manipulation task that you need to do in pretty much any data analysis is recode data.  It’s almost never the case that the data are set up exactly the way you need them for your analysis.

In R, you can re-code an entire vector or array at once. To illustrate, let’s set up a vector that has missing values.

A <- c(3, 2, NA, 5, 3, 7, NA, NA, 5, 2, 6)

A

[1] 3 2 NA 5 3 7 NA NA 5 2 6

We can re-code all missing values by another number (such as zero) as follows: [click to continue…]

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