unsupported/test/cxx11_tensor_broadcasting.cpp

// This file is part of Eigen, a lightweight C++ template library
// for linear algebra.
//
// Copyright (C) 2014 Benoit Steiner <benoit.steiner.goog@gmail.com>
//
// This Source Code Form is subject to the terms of the Mozilla
// Public License v. 2.0. If a copy of the MPL was not distributed
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.

#include "main.h"

#include <Eigen/CXX11/Tensor>

using Eigen::Tensor;

static void test_simple_broadcasting()
{
  Tensor<float, 4> tensor(2,3,5,7);
  tensor.setRandom();
  array<ptrdiff_t, 4> broadcasts;
  broadcasts[0] = 1;
  broadcasts[1] = 1;
  broadcasts[2] = 1;
  broadcasts[3] = 1;

  Tensor<float, 4> no_broadcast;
  no_broadcast = tensor.broadcast(broadcasts);

  VERIFY_IS_EQUAL(no_broadcast.dimension(0), 2);
  VERIFY_IS_EQUAL(no_broadcast.dimension(1), 3);
  VERIFY_IS_EQUAL(no_broadcast.dimension(2), 5);
  VERIFY_IS_EQUAL(no_broadcast.dimension(3), 7);

  for (int i = 0; i < 2; ++i) {
    for (int j = 0; j < 3; ++j) {
      for (int k = 0; k < 5; ++k) {
        for (int l = 0; l < 7; ++l) {
          VERIFY_IS_EQUAL(tensor(i,j,k,l), no_broadcast(i,j,k,l));
        }
      }
    }
  }

  broadcasts[0] = 2;
  broadcasts[1] = 3;
  broadcasts[2] = 1;
  broadcasts[3] = 4;
  Tensor<float, 4> broadcast;
  broadcast = tensor.broadcast(broadcasts);

  VERIFY_IS_EQUAL(broadcast.dimension(0), 4);
  VERIFY_IS_EQUAL(broadcast.dimension(1), 9);
  VERIFY_IS_EQUAL(broadcast.dimension(2), 5);
  VERIFY_IS_EQUAL(broadcast.dimension(3), 28);

  for (int i = 0; i < 4; ++i) {
    for (int j = 0; j < 9; ++j) {
      for (int k = 0; k < 5; ++k) {
        for (int l = 0; l < 28; ++l) {
          VERIFY_IS_EQUAL(tensor(i%2,j%3,k%5,l%7), broadcast(i,j,k,l));
        }
      }
    }
  }
}


static void test_vectorized_broadcasting()
{
  Tensor<float, 3> tensor(8,3,5);
  tensor.setRandom();
  array<ptrdiff_t, 3> broadcasts;
  broadcasts[0] = 2;
  broadcasts[1] = 3;
  broadcasts[2] = 4;

  Tensor<float, 3> broadcast;
  broadcast = tensor.broadcast(broadcasts);

  VERIFY_IS_EQUAL(broadcast.dimension(0), 16);
  VERIFY_IS_EQUAL(broadcast.dimension(1), 9);
  VERIFY_IS_EQUAL(broadcast.dimension(2), 20);

  for (int i = 0; i < 16; ++i) {
    for (int j = 0; j < 9; ++j) {
      for (int k = 0; k < 20; ++k) {
        VERIFY_IS_EQUAL(tensor(i%8,j%3,k%5), broadcast(i,j,k));
      }
    }
  }

  tensor.resize(11,3,5);
  tensor.setRandom();
  broadcast = tensor.broadcast(broadcasts);

  VERIFY_IS_EQUAL(broadcast.dimension(0), 22);
  VERIFY_IS_EQUAL(broadcast.dimension(1), 9);
  VERIFY_IS_EQUAL(broadcast.dimension(2), 20);

  for (int i = 0; i < 22; ++i) {
    for (int j = 0; j < 9; ++j) {
      for (int k = 0; k < 20; ++k) {
        VERIFY_IS_EQUAL(tensor(i%11,j%3,k%5), broadcast(i,j,k));
      }
    }
  }
}


void test_cxx11_tensor_broadcasting()
{
   CALL_SUBTEST(test_simple_broadcasting());
   CALL_SUBTEST(test_vectorized_broadcasting());
}