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applying a function over an array

3 messages · BJ, Gabor Grothendieck

BJ
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Is there a way to apply a function with several arguements over an 
array? For instance if you had a function d<-function(a,b,c) {a+b+c} and 
a 4,3 array, could you apply the function over each line of the array? 
tapply seems to only allow one argument, and I just can't think of a way 
to explicitly tell R that I am passing it 3 distinct objects instead of 
1 complex one.  Thank you as always for your help. ~Erithid
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On 5/18/05, BJ <erithid at bellsouth.net> wrote:
If x is the 4x3 array:

mapply(d, x[,1], x[,2], x[,3])
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On 5/18/05, Gabor Grothendieck <ggrothendieck at gmail.com> wrote:
Also you might check if your d is vectorized already (it is in your 
example) in which case you can just do:

   d(x[,1], x[,2], x[,3])