[R] min rows multiplication by the max rows

[Rui Barradas]

Hello,

I have just found out that you are cross posting [1].
Please do not cross post, ask a question, wait for an answer and after 
or 3 days, if you don't have a (satisfactory) answer, ask somewhere else.

[1] 
https://stackoverflow.com/questions/61973737/min-rows-multiplication-by-the-max-rows


Rui Barradas

Às 15:52 de 23/05/20, Rui Barradas escreveu:
> Hello,
> 
> Use ?apply on each of the matrices.
> 
> 
> min_max <- function(X, Y, na.rm = FALSE){
>    Min <- apply(X, 1, min, na.rm = na.rm)
>    Max <- apply(Y, 1, max, na.rm = na.rm)
>    Min*Max
> }
> min_max(M, N)
> #[1] 4 3 4
> 
> 
> Hope this helps,
> 
> Rui Barradas
> 
> Às 15:30 de 23/05/20, Vahid Borji escreveu:
>> Hi my R friends,
>>
>> I have two matrices as follows:
>>
>> M<-matrix(c(1,4,1,3,1,4,2,3,1,2,1,2),3)
>>
>> 1    3    2    2
>> 4    1    3    1
>> 1    4    1    2
>>
>> N<-matrix(c(1,1,2,2,3,4,-2,2,1,4,3,-1),3)
>>
>> 1    2   -2    4
>> 1    3    2    3
>> 2    4    1   -1
>>
>> I want to find a vector which is a matrix 1*3 and each of its elements is
>> the multiplication of min element of each row of M by the max element of
>> the corresponding row of N (for example, the first element of the 
>> vector is
>> the min element of the first row of matrix M, which is 1, multiply by the
>> max element of the first row of matrix N, which is 4, and so the first
>> element of the vector is 1*4 which is 4).
>> The final answer is: (1*4, 1*3,1*4)=(4,3,4)
>>
>> To find this vector (or matrix) I have written the below code:
>> c(min(M[1,])*max(N[1,]),min(M[2,])*max(N[2,]),min(M[3,])*max(N[3,]))
>> But it is so long. could anyone writes a shorter (or simpler, or easier)
>> code?
>>
>>     [[alternative HTML version deleted]]
>>
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>> http://www.R-project.org/posting-guide.html
>> and provide commented, minimal, self-contained, reproducible code.
>>
> 
> ______________________________________________
> R-help using r-project.org mailing list -- To UNSUBSCRIBE and more, see
> 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.