[R] question

[R. Michael Weylandt]

Sorry about that -- forgot the case where you might only have a
certain entry once: try this,

sapply(split(GS, rownames(GS)), function(x) colSums(as.matrix(x)))

or

sapply(split(GS, rownames(GS)), function(x) if(is.matrix(x)) colSums(x) else x)

I'm not sure if there's a way to force split to give you matrix
elements back but it would be nice.

Michael

PS -- It's nice to cc the list on follow up questions as well so
others have a chance to answer and you get a quicker reply (since
there are R-helpers in most every timezone, many of whom know much
more R-fu than me.)

On Wed, Feb 15, 2012 at 4:46 AM, Soheila Khodakarim
<lkhodakarim at gmail.com> wrote:
> Hi,
>
> thanks for your guid.
> But when I used it I saw this error
>
> sapply(split(GS,rownames(GS)), colSums)
> Error in FUN(X[[1L]], ...) :
>   'x' must be an array of at least two dimensions
>
> Is there any command to do split but keep type of data(Matrix)?
>
> Regards,
> Soheila
>
>
>
>
>
>
>
>
>
>
>
> On Tue, Feb 14, 2012 at 1:12 PM, R. Michael Weylandt
> <michael.weylandt at gmail.com> wrote:
>>
>> Perhaps something (untested) like
>>
>> sapply(split(x, rownames(x)), colSums)
>>
>> Next time it's suggested you use dput() to send your data.
>>
>> Michael
>>
>> On Tue, Feb 14, 2012 at 7:08 AM, Soheila Khodakarim
>> <lkhodakarim at gmail.com> wrote:
>> > I have this matrix in R,
>> >
>> >
>> >   s1 s2 s3 s4
>> > g1  1  0  0  0
>> > g1  0  1  0  0
>> > g1  0  0  1  0
>> > g2  1  0  0  0
>> > g2  0  1  0  0
>> > g3  1  0  0  0
>> > g4  0  0  1  0
>> > g4  1  0  0  0
>> > g4  0  1  0  0
>> > g4  0  0  0  1
>> >
>> >
>> > I want to split this matrix based on its rows then sum based on columns,
>> > finally I want to make this matrix:
>> >
>> >   s1 s2 s3 s4
>> > g1  1  1  1  0
>> > g2  1  1  0  0
>> > g3  1  0  0  0
>> > g4  1  1  1  1
>> >
>> > I will appreciate if you guide me.
>> >
>> > Regards,
>> > Soheila
>> >
>> >        [[alternative HTML version deleted]]
>> >
>> > ______________________________________________
>> > R-help at r-project.org mailing list
>> > https://stat.ethz.ch/mailman/listinfo/r-help
>> > PLEASE do read the posting guide
>> > http://www.R-project.org/posting-guide.html
>> > and provide commented, minimal, self-contained, reproducible code.
>
>