[R] column removing under certain conditions

[Ivan Calandra]

Dear Martin,

I'm not sure I understood you well, because you basically have the 
answer already...

What about this?
A[,apply(A, 2, function(x) median(x)>0), drop=FALSE]

(drop=FALSE ensures that you keep it as column even if only one column 
is selected)

HTH,
Ivan

Le 3/4/2011 11:11, Scheuringer Martin a écrit :
> Dear collegues!
>
>
> Given a matrix, I would like to remove columns, that do not fulfill a certain condition. The condition is, that the median of the column is higher than a certain value.
>
> I've seen the help on removing NA columns, but I cannot figure out how to change the function part of the statement, so that the function is only TRUE if the median of the column is higher than x;
>
> A[,apply(A, 2, function(x) all(x>=0))]
>
>
> Thank you very much,
> Regards!
>
>
>
> Martin Scheuringer
>
> ---------------------------------
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-- 
Ivan CALANDRA
PhD Student
University of Hamburg
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ivan.calandra at uni-hamburg.de

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