find max value in each row and return column number and column name

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!
cbind(a, max=apply(a,1,max),
         max.col.num =apply(a,1,which.max) ,
         max.col.name= names(a)[apply(a,1,which.max)]  )
Thank you!

Gary

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find max value in each row and return column number and column name

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