Search values and create a new matrix
On Nov 4, 2009, at 4:45 PM, Jose Narillos de Santos wrote:
Hi You wrotte me in R help and I?m very gratefull. I couldn?t reply because an illness. I writte this to see if you can help to solve. I?m a begginer (I?m 20 years old ) but I?m trying to learn more about this program also I?m learning Octave. I need to create a matrix in R whose values depends on the values of other matrix. You see: I have a first "R" matrix whose first row and first colum are a "key/ title" in my case numbers. Imagine R has a size N,M The second matrix "Z" has an N-1,2 size. In this new matrix the second column on Z is equal to the first column on R. The first column has numbers "desordered" but that will appear on the first row on R. Each pair on Z (in example row 2 and colum 2) is a point in R. I want to create a code that searches the values on each row and colum on Z and create a new matrix "F" whose size is (N-1,1) and whose values are each cross value on R. In example: R= 0 12 14 16 1 2 3 6 2 5 5 2 3 6 5 2 Z= 1 14 2 12 3 16
> apply(Z, 1, function(x) R[x[1]+1, which(R[1, ]==x[2]) ] ) [1] 3 5 2
The result should be: F= 3 5 (point for example is the second row first colum on R) 2 You can guide me? Sorry for all and many thans I?m getting crazy... In excel there is a function Search H or Search V similar but only on dimension not both dimmensions... [[alternative HTML version deleted]]
______________________________________________ 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.
David Winsemius, MD Heritage Laboratories West Hartford, CT