R help - Jul 2009 - problem with merging matrices

Dear all,

I'm a relative new user of R and I have a problem with merging a collection
of matrices. All matrices in this collection have the same dimension (532
rows and 532 columns), but can differ in the row and columns names. I'd like
to merge these matrices in such a way that the resulting matrix only
contains unique row- and column-names and that in case of a match between
the row or column names the smallest value is retained.

As an example says more:

A1<-matrix(c(1:9), ncol=3, byrow=TRUE)
rownames(A1)<-colnames(A1)<-c("a","b","c")
A1

  a b c
a 1 2 3
b 4 5 6
c 7 8 9

A2<-matrix(c(7,1,3,10,2,7,3,1,8),ncol=3,byrow=TRUE)
rownames(A2)<-colnames(A2)<-c("a","y","z")
A2

   a y z
a  7 1 3
y 10 2 7
z  3 1 8


I want something like this to be returned:

   a    b    c    y    z
a  1   2    3    1    3
b  4   5    6    NA NA
c  7   8    9    NA NA
y  10 NA NA  5    6
z  3  NA  NA  8    9

Many thanks,

Jurgen

I'm using: R-2.9.1 (2009-06-26) on a windows XP platform.

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On Wednesday, July 15, 2009 8:28 AM, jurgen claesen wrote:

 > ...I'm a relative new user of R and I have a
 > problem  with  merging   a   collection   of
 > matrices.  All  matrices  in this collection
 > have the same dimension (532  rows  and  532
 > columns),  but  can  differ  in  the row and
 > columns  names.  I'd  like  to  merge  these
 > matrices  in  such  a way that the resulting
 > matrix   only   contains   unique  row-  and
 > column-names and that in  case  of  a  match
 > between the row or column names the smallest
 > value is retained....
 >    As an example says more:
 >
 >    A1<-matrix(c(1:9), ncol=3, byrow=TRUE)
 >   
rownames(A1)<-colnames(A1)<-c("a","b","c")
 >
 >      a b c
 >    a 1 2 3
 >    b 4 5 6
 >    c 7 8 9
 >
 >    A2<-matrix(c(7,1,3,10,2,7,3,1,8),ncol=3,byrow=TRUE)
 >   
rownames(A2)<-colnames(A2)<-c("a","y","z")
 >
 >       a y z
 >    a  7 1 3
 >    y 10 2 7
 >    z  3 1 8
 >
 >    I want something like this to be returned:
 >
 >        a  b  c  y  z
 >    a   1  2  3  1  3
 >    b   4  5  6 NA NA
 >    c   7  8  9 NA NA
 >    y  10 NA NA  5  6
 >    z   3 NA NA  8  9
 >

Two questions (a) how do you want to decide which of the
elements gets dropped out---like the value 7 in A2 [1,1] above
and (b) what goes in the bottom corner of the new matrix? I
would have guessed i would have seen
   2 7
   1 8
in the corner.  Was that a typo or do you really want to
overwrite the values of the submatrix that *is* in A1?

david


--
 David
?
 -----------------------------------------------------
 David Huffer, Ph.D.               Senior Statistician
 CSOSA/Washington, DC           david.huffer at csosa.gov