Getting warning using setAs() to specify colClasses in R [closed]

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Closed 6 years ago.

I tried using the answer @Greg Snow provided in this question, but I keep getting a warning regardless of what I do. Can someone help with this:?

> setAs("character","myDate",function(from) as.Date(from, format="%b %d, %Y %r"))
in method for ‘coerce’ with signature ‘"character","myDate"’: no definition for class “myDate”

I wanted to make sure that the "methods" package is load (it looks like setAs depends on it) and I got this:

> getOption("defaultPackages")
[1] "datasets"  "utils"     "grDevices" "graphics"  "stats"     "methods"

TIA

来源：https://stackoverflow.com/questions/14146341/getting-warning-using-setas-to-specify-colclasses-in-r