From octave-sources-request at bevo dot che dot wisc dot edu  Mon Jun 26 08:54:26 2000
Subject: blkdiag.m (Re:matlab compatibility)
From: Daniel Calvelo <dcalvelo at pharion dot univ-lille2 dot fr>
To: octave-sources at bevo dot che dot wisc dot edu
Date: Mon, 26 Jun 2000 15:02:28 +0200 (CET)


In http://www.che.wisc.edu/octave/mailing-lists/octave-sources/2000/93, 
pkienzle at kienzle dot powernet dot co dot uk remarks:

[snip]
.
. Matrix manipulation.
    reshape     - Change size.
    diag        - Diagonal matrices and diagonals of matrix.
x   blkdiag     - Block diagonal concatenation.
[snip]

There you are :)

----------------------------------blkdiag.m----------------------------
function y = blkdiag(...),
  ## Build a block-diagonal matrix from all the arguments
  ## Daniel Calvelo 2000. Use, modify and debug at will
  nin = 0;
  va_start();
  sizes = zeros( nargin, 2 );
  while( ++nin <= nargin ),
    m = va_arg();
    if ~isnumeric( m ),
      error("Non-numeric argument found.");
    endif
    sizes(nin,:) = size( m );
  endwhile
  csz = [[0 0];cumsum(sizes)]
  y = zeros( max(csz) );
  va_start();
  nin = 0;
  while(++nin <= nargin),
    y(csz(nin,1)+1:csz(nin+1,1) , csz(nin,2)+1:csz(nin+1,2)) = va_arg();
  endwhile
endfunction
------------------------------------------------------------------------


-- Daniel Calvelo Aros
     calvelo at lifl dot fr



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