[R] find max value in each row and return column number and column name

[Clint Bowman]

?which.max should start you down the right path

Clint Bowman			INTERNET:	clint at ecy.wa.gov
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On Fri, 1 Nov 2013, Gary Dong wrote:

> Dear R users,
>
> I wonder how I can use R to identify the max value of each row, the column
> number column name:
>
> For example:
>
> a <- data.frame(x = rnorm(4), y = rnorm(4), z = rnorm(4))
>
>> a
>           x          y          z
> 1 -0.7289964  0.2194702 -2.4674780
> 2  1.0889353  0.3167629 -0.9208548
> 3 -0.6374692 -1.7249049  0.6567313
> 4 -0.1348642  0.4507473 -1.7309010
>
> In this data frame, I compare y and z only.
>
> What I need:
>
>            x                     y                     z
> max                 max.col.num         max.col.name
> 1 -0.7289964  0.2194702 -2.4674780         0.2194702               2
>                     y
> 2  1.0889353  0.3167629 -0.9208548         0.3167629               2
>                     y
> 3 -0.6374692 -1.7249049  0.6567313         0.6567313               3
>                    z
> 4 -0.1348642  0.4507473 -1.7309010         0.4507473               2
>                    y
>
>
> Any suggestion will be greatly appreciated!
>
> Thank you!
>
> Gary
>
> 	[[alternative HTML version deleted]]
>
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