mps-0.0.0
MatrixProductStatesinC++
 All Data Structures Namespaces Functions Variables Enumerations Enumerator Groups Pages
cmps_to_vector.cc
1 // -*- mode: c++; fill-column: 80; c-basic-offset: 2; indent-tabs-mode: nil -*-
2 /*
3  Copyright (c) 2010 Juan Jose Garcia Ripoll
4 
5  Tensor is free software; you can redistribute it and/or modify it
6  under the terms of the GNU Library General Public License as published
7  by the Free Software Foundation; either version 2 of the License, or
8  (at your option) any later version.
9 
10  This program is distributed in the hope that it will be useful,
11  but WITHOUT ANY WARRANTY; without even the implied warranty of
12  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13  GNU Library General Public License for more details.
14 
15  You should have received a copy of the GNU General Public License along
16  with this program; if not, write to the Free Software Foundation, Inc.,
17  51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
18 */
19 
20 #include <algorithm>
21 #include <mps/mps.h>
22 
23 namespace mps {
24 
25  using namespace tensor;
26 
27  const CTensor mps_to_vector(const CMPS &mps)
28  {
29  assert(mps.size() > 0);
30 
31  CTensor output = mps[0];
32  index d0 = output.dimension(0);
33  index d = output.dimension(1);
34  for (index i = 1; i < mps.size(); i++) {
35  output = fold(output, -1, mps[i], 0);
36  output = reshape(output, d0, output.dimension(1)*output.dimension(2), output.dimension(3));
37  }
38  return trace(output, 0, -1);
39  }
40 
41 } // namespace mps
Real matrix product structure.
Definition: cmps.h:31
const RTensor mps_to_vector(const RMPS &mps)
Convert a RMPS to a complex vector, contracting all tensors.