Re: [R] using nrow to identify one row

From: Gabor Csardi <csardi_at_rmki.kfki.hu>
Date: Fri, 14 Mar 2008 21:53:17 +0100

Try

temp[1,,drop=FALSE]

See ?"[" for the explanation.

Gabor

On Fri, Mar 14, 2008 at 04:46:10PM -0400, Gregory Gentlemen wrote:
> Hi fellow R-users,
>
> I have run into a problem when trying to identify the number of rows in a matrix. Say we have an arbitrary 5 by 5 matrix called temp:
>
> temp <- matrix(norm(25), nrow=5)
>
> The problem is that nrow(temp[1,]) returns NULL. I would like it to return 1 because in my larger program I am indexing the rows of large matrices according to another variable and I need to test when the resulting matrices have 0, 1 or more rows.
>
> Thanks in advance for any assistance.
>
> Best regards,
> Gregory Gentlemen
>
>
>
>
> ---------------------------------
>
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>
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-- 
Csardi Gabor <csardi_at_rmki.kfki.hu>    UNIL DGM

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Received on Fri 14 Mar 2008 - 20:59:44 GMT

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