[R] forcing apply() to return data frame

Thomas Lumley tlumley at u.washington.edu
Fri Apr 21 16:37:45 CEST 2006

On Fri, 21 Apr 2006, Federico Calboli wrote:

> Hi All,
> I am (almost) successfully using apply() to apply a function recursively
> on a data matrix. The function is question is as.genotype() from the
> library 'genetics'
> apply(subset(chr1, names$breed == 'lab'),2,as.genotype,sep ="")
> Unfortuantely apply puts it's results into a matrix object rather than a
> data frame, tranforming my factors into numerics and making the results
> useless.
> Is there a way of forcing apply() to return a data frame rather than a
> matrix?

The conversion to a matrix happens on the way in to apply, not on the way 
out, so no.


Thomas Lumley			Assoc. Professor, Biostatistics
tlumley at u.washington.edu	University of Washington, Seattle

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