matrix merge problem

Merci a lot!!!!!!

On Tue, Apr 14, 2009 at 10:32 PM, Luc Villandre 
<villandl at dms.umontreal.ca <mailto:villandl at dms.umontreal.ca>> wrote:

    Hi Juan,

    Your first question can be answered easily.

    bin.matrix = matrix(A %in% B,nrow(A),ncol(A)) ;
    bin.vector = rowSums(bin.matrix) > 0 ;
    C = A[bin.vector,] ;

    This should do the trick.

    Cheers,

    Luc

    Juan Pablo Fededa wrote:

        Dear r-help contributors,

        I have two questions:

        first:

        I have a matrix A and a vector B.
        I want to make a new matrix C, which is made of the rows of A
        having a value
        included in B.

        Second:

        I have two matrixes A and B, of different dimensions.
        B has unique values in column 2 and A has not unique values on
        column 2.
        I want to merge this two matrixes by the values in the columns
        2 of B and 2
        of A in such a way that the resulting matrix will be C:


        A:

        1 2
        2 2
        3 3
        4 3
        5 4
        6 4
        7 5
        8 5


        B:

        1 2  x c d
        2 3  y f  g

        C:

        1 2  x c d
        2 2  x c d
        3 3  y f  g
        4 3  y f  g
        5 4 NA NA
        6 4 NA NA
        7 5 NA NA
        8 5 NA NA


        Can you help me?


        Many thanks in advance.

               [[alternative HTML version deleted]]