[R] Removing columns that are all NA from a matrix

[Chuck Cleland]

On 2/14/2008 7:59 AM, Martin Waller wrote:
> Hi,
> 
> I guess this might be a FAQ or something, and there's probably a nice 
> simple way to do it, but I can't think of it:
> 
> Given a matrix, I want to remove columns that are _entirely_ filled with 
> NAs (partial NAs are fine).
> 
> How please?

mymat[,which(colMeans(is.na(mymat)) < 1)]

> Thanks,
> 
> Martin
> 
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-- 
Chuck Cleland, Ph.D.
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