[R] Counting in Matrix

[Erik Iverson]

?rowSums

> -----Original Message-----
> From: r-help-bounces at r-project.org [mailto:r-help-bounces at r-project.org]
> On Behalf Of Tom Pitt
> Sent: Tuesday, December 15, 2009 2:57 PM
> To: r-help at r-project.org
> Subject: [R] Counting in Matrix
> 
> 
> Hi All,
> 
> Is there an easy way to count "TRUEs" for each row?
> 
> Thanks,
> Tom
> 
> 
>       x1    x2    x3    x4
> 1   TRUE  TRUE  TRUE  TRUE
> 2  FALSE  TRUE  TRUE  TRUE
> 3   TRUE FALSE  TRUE  TRUE
> 4  FALSE FALSE  TRUE  TRUE
> 5   TRUE  TRUE FALSE  TRUE
> 6  FALSE  TRUE FALSE  TRUE
> 7   TRUE FALSE FALSE  TRUE
> 8  FALSE FALSE FALSE  TRUE
> 9   TRUE  TRUE  TRUE FALSE
> 10 FALSE  TRUE  TRUE FALSE
> 11  TRUE FALSE  TRUE FALSE
> 12 FALSE FALSE  TRUE FALSE
> 13  TRUE  TRUE FALSE FALSE
> 14 FALSE  TRUE FALSE FALSE
> 15  TRUE FALSE FALSE FALSE
> --
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> tp964644p964644.html
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