%
% @file gb_mat.m
%
% @brief
%
% @copyright
% Copyright (©) 2021 EPFL (Ecole Polytechnique Fédérale de Lausanne)
% SPC (Swiss Plasma Center)
%
% SPClibs is free software: you can redistribute it and/or modify it under
% the terms of the GNU Lesser General Public License as published by the Free
% Software Foundation, either version 3 of the License, or (at your option)
% any later version.
%
% SPClibs 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 Lesser General Public License
% along with this program. If not, see <https://www.gnu.org/licenses/>.
%
% @author
% (in alphabetical order)
% @author Trach-Minh Tran <trach-minh.tran@epfl.ch>
%
function [mata] = gb_mat(file, dset)
rank=h5readatt(file, dset, 'RANK');
ku=h5readatt(file, dset, 'KU');
kl=h5readatt(file, dset, 'KL');
gbmat=h5read(file, dset);
m=rank; n=rank;
mata = zeros(m,n);
for i=1:m
    jmin = max(1,i-kl);
    jmax = min(n,i+ku);
    for j=jmin:jmax
        ib = kl+ku+i-j+1;
        mata(i,j)=gbmat(ib,j);
    end
end
clear gbmat;