function [f]=comp_isepdgtreal(coef,g,L,a,M,phasetype)
%COMP_ISEPDGTREAL  Separable IDGT.
%   Usage:  f=comp_isepdgtreal(c,g,L,a,M);
%       
%   This is a computational routine. Do not call it directly.
%
%   Input must be in the M x N x W format, so the N and W dimension is
%   combined.
%
%   See also: idgt
%
%   Url: http://ltfat.github.io/doc/comp/comp_isepdgtreal.html

% Copyright (C) 2005-2016 Peter L. Soendergaard <peter@sonderport.dk>.
% This file is part of LTFAT version 2.1.2
%
% 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 3 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, see <http://www.gnu.org/licenses/>.

%   AUTHOR : Peter L. Søndergaard.
%   TESTING: OK
%   REFERENCE: OK

Lwindow=size(g,1);

if phasetype==1
    % Change from time-invariant phase convention to a
    % frequency-invariant one
    b=L/M;
    M2=floor(M/2)+1;
    N=size(coef,2);
    %M2short=ceil(M/2);

    TimeInd = (0:(N-1))/N;
    FreqInd = (0:(M2-1))*b;

    phase = FreqInd'*TimeInd;
    phase = exp(-2*1i*pi*phase);

    % Handle multisignals
    coef = bsxfun(@times,coef,phase);
end;


if L==Lwindow
    % Do full-window algorithm.

    % Call the computational subroutine.
    f = comp_idgtreal_long(coef,g,L,a,M);

else
    % Do filter bank algorithm.
    % Call the computational subroutine.
    f = comp_idgtreal_fb(coef,g,L,a,M);
end;

