[R] extracting max row from data matrix

[Adam D. I. Kramer]

Hi Srini,

This may be as simple as tapply(weight,fruit,max)

or t(that) if you want it as you specified.

--Adam

On Sun, 7 Sep 2008, Srinivas Iyyer wrote:

> dear group,
> i have a data matrix with some replicate items with different values. I want to extract the row with max value.
>
> for example:
>> x
>   fruit weight
> 1  apple    1.3
> 2  apple    1.5
> 3  apple    1.6
> 4 orange    1.4
> 5 orange    1.6
>
>
> x is a data frame.
> I want to extract unique items from fruits that has max weight.
>
> that is:
>
> 3  apple    1.6
> 5 orange    1.6
>
> I want to be able to use apply functions. Could some one lend some help please.
>
> Thanks
> srini
>
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