[R] Array arithmetic

[Benilton Carvalho]

no, it won't.

you're doing the right math on the "valid" subset... but you're not  
returning the zeros where needed.... therefore, the whole thing will  
get recycled to match the dimensions.

b

On Mar 6, 2008, at 2:03 PM, Henrique Dallazuanna wrote:

> I think this should work:
>
> array(A[abs(B) > 10e-5]/B[abs(B) > 10e-5], dim=c(L, M, N, P))
>
> On 06/03/2008, Gang Chen <gangchen6 at gmail.com> wrote:
>> I have two arrays A and B with dimensions of (L, M, N, P) and (L, M,
>> N), and I want to do
>>
>> for (i in 1:L) {
>> for (j in 1:M) {
>> for (k in 1:N) {
>>   if (abs(B[i, j, k]) > 10e-5)  C[i, j, k,] <- A[i, j, k,]/B[i, j, k]
>>   else C[i, j, k,] <- 0
>> }
>> }
>> }
>>
>> How can I get C more efficiently than looping?
>>
>> Thanks,
>> Gang
>>
>> ______________________________________________
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>> https://stat.ethz.ch/mailman/listinfo/r-help
>> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
>
>
> -- 
> Henrique Dallazuanna
> Curitiba-Paraná-Brasil
> 25° 25' 40" S 49° 16' 22" O
>
> ______________________________________________
> R-help at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide http://www.R-project.org/posting-guide.html
> and provide commented, minimal, self-contained, reproducible code.