% FROMPACK Converts a cone problem in SDPPACK format to SEDUMI format.
%
% [At,c] = frompack(A,b,C,blk)  Given a problem (A,b,C,blk) in the
%   SDPPACK-0.9-beta format, this produces At and c for use with
%   SeDuMi. This lets you execute
%
% [x,y,info] = SEDUMI(At,b,c,blk);
%
% IMPORTANT: this function assumes that the SDPPACK function `smat'
%    exists in your search path.
%
% SEE ALSO sedumi.

function [At,c] = frompack(A,b,C,blk)
%
% This file is part of SeDuMi 1.1 by Imre Polik and Oleksandr Romanko
% Copyright (C) 2005 McMaster University, Hamilton, CANADA  (since 1.1)
%
% Copyright (C) 2001 Jos F. Sturm (up to 1.05R5)
%   Dept. Econometrics & O.R., Tilburg University, the Netherlands.
%   Supported by the Netherlands Organization for Scientific Research (NWO).
%
% Affiliation SeDuMi 1.03 and 1.04Beta (2000):
%   Dept. Quantitative Economics, Maastricht University, the Netherlands.
%
% Affiliations up to SeDuMi 1.02 (AUG1998):
%   CRL, McMaster University, Canada.
%   Supported by the Netherlands Organization for Scientific Research (NWO).
%
% This program is free software; you can redistribute it and/or modify
% it under the terms of the GNU General Public License as published by
% the Free Software Foundation; either version 2 of the License, or
% (at your option) any later version.
%
% This program is distributed in the hope that it will be useful,
% but WITHOUT ANY WARRANTY; without even the implied warranty of
% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
% GNU General Public License for more details.
%
% You should have received a copy of the GNU General Public License
% along with this program; if not, write to the Free Software
% Foundation, Inc.,  51 Franklin Street, Fifth Floor, Boston, MA
% 02110-1301, USA%

m = length(b);
% ----------------------------------------
% In SDPPACK, 0s are sometimes used  as emptyset and vice versa.
% ----------------------------------------
if blk.l == 0
    A.l = []; C.l = [];
end
if isempty(blk.q)
    A.q = []; C.q = [];
end
if isempty(blk.s)
    A.s = []; C.s = [];
end
% ----------------------------------------
% SDP:
% ----------------------------------------
Asdp = [];
if sum(blk.s) == 0
    csdp = [];
else
    for i=1:m
        Asdp = [Asdp blk2vec( smat(sparse(A.s(i,:)),blk.s), blk.s ) ];
    end
    csdp = blk2vec(C.s,blk.s);
end
% ----------------------------------------
% Assemble LP, LORENTZ and SDP.
%----------------------------------------
At = [A.l'; A.q'; Asdp];
c = [C.l; C.q; csdp];
