Thanks a lot Baptiste & Dimitris,

It's working!

Cheers,
Umesh

On Wed, Apr 29, 2009 at 2:06 PM, Dimitris Rizopoulos <
d.rizopoulos@erasmusmc.nl> wrote:

> probably you want to use seq(), e.g.,
>
> mat <- matrix(1:500, 100, 5)
>
> mat[seq(1, nrow(mat), 2), ]
> mat[seq(1, nrow(mat), 3), ]
> mat[seq(1, nrow(mat), 4), ]
>
>
> I hope it helps.
>
> Best,
> Dimitris
>
>
> Umesh Srinivasan wrote:
>
>> Hi all,
>>
>> If  I have a huge matrix/ dataframe and I want to create a new matrix/
>> dataframe with every second (or third, or fourth etc.) row of the original
>> matrix, how can I do it? Any help much appreciated.
>>
>> Thanks,
>> Umesh
>>
>>        [[alternative HTML version deleted]]
>>
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>> PLEASE do read the posting guide
>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>>
> --
> Dimitris Rizopoulos
> Assistant Professor
> Department of Biostatistics
> Erasmus University Medical Center
>
> Address: PO Box 2040, 3000 CA Rotterdam, the Netherlands
> Tel: +31/(0)10/7043478
> Fax: +31/(0)10/7043014
>

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