Add unit-test for reshape

- add unittest for dynamic & fixed-size reshape
- fix fixed-size reshape bugs bugs found while testing

Eigen/src/Core/Reshape.h

@@ -3,6 +3,7 @@
 //
 // Copyright (C) 2008 Gael Guennebaud <gael.guennebaud@inria.fr>
 // Copyright (C) 2006-2010 Benoit Jacob <jacob.benoit.1@gmail.com>
+// Copyright (C) 2014 yoco <peter.xiau@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
@@ -242,8 +243,8 @@ template<typename XprType, int ReshapeRows, int ReshapeCols, bool InnerPanel, bo
     inline Scalar& coeffRef(Index index)
     {
       EIGEN_STATIC_ASSERT_LVALUE(XprType)
-      const RowCol row_col = index_remap((RowsAtCompileTime == 1 ? 0 : index)
+      const RowCol row_col = index_remap(RowsAtCompileTime == 1 ? 0 : index,
-                                       (RowsAtCompileTime == 1 ? index : 0));
+                                         RowsAtCompileTime == 1 ? index : 0);
       return m_xpr.const_cast_derived().coeffRef(row_col.first, row_col.second);
 
     }
@@ -251,16 +252,16 @@ template<typename XprType, int ReshapeRows, int ReshapeCols, bool InnerPanel, bo
     EIGEN_DEVICE_FUNC
     inline const Scalar& coeffRef(Index index) const
     {
-      const RowCol row_col = index_remap((RowsAtCompileTime == 1 ? 0 : index)
+      const RowCol row_col = index_remap(RowsAtCompileTime == 1 ? 0 : index,
-                                       (RowsAtCompileTime == 1 ? index : 0));
+                                         RowsAtCompileTime == 1 ? index : 0);
       return m_xpr.const_cast_derived().coeffRef(row_col.first, row_col.second);
     }
 
     EIGEN_DEVICE_FUNC
     inline const CoeffReturnType coeff(Index index) const
     {
-      const RowCol row_col = index_remap((RowsAtCompileTime == 1 ? 0 : index)
+      const RowCol row_col = index_remap(RowsAtCompileTime == 1 ? 0 : index,
-                                       (RowsAtCompileTime == 1 ? index : 0));
+                                         RowsAtCompileTime == 1 ? index : 0);
       return m_xpr.coeff(row_col.first, row_col.second);
     }
 

test/CMakeLists.txt

@@ -150,6 +150,7 @@ ei_add_test(exceptions)
 ei_add_test(redux)
 ei_add_test(visitor)
 ei_add_test(block)
+ei_add_test(reshape)
 ei_add_test(corners)
 ei_add_test(product_small)
 ei_add_test(product_large)

test/reshape.cpp

@@ -0,0 +1,58 @@
+// This file is part of Eigen, a lightweight C++ template library
+// for linear algebra.
+//
+// Copyright (C) 2014 yoco <peter.xiau@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"
+
+using Eigen::Map;
+using Eigen::MatrixXi;
+
+void dynamic_reshape_all_size(int row, int col) {
+  // create matrix(row, col) and filled with 0, 1, 2, ...
+  Eigen::MatrixXi m(row, col);
+  for(int r = 0; r < row; ++r)
+    for(int c = 0; c < col; ++c)
+      m(r, c) = col * c + r;
+
+  // for all possible shape
+  for(int new_r = 1; new_r <= row * col; ++new_r) {
+    // skip invalid shape
+    if(row * col % new_r != 0)
+      continue;
+
+    // reshape and compare
+    int new_c = row * col / new_r;
+    VERIFY_IS_EQUAL(m.reshape(new_r, new_c),
+                    Map<MatrixXi>(m.data(), new_r, new_c));
+  }
+}
+
+// just test a 4x4 matrix, enumerate all combination manually,
+// so I don't have to do template-meta-programming here.
+void static_reshape_all_size() {
+  // create matrix(row, col) and filled with 0, 1, 2, ...
+  int row = 4;
+  int col = 4;
+  Eigen::MatrixXi m(row, col);
+  for(int r = 0; r < row; ++r)
+    for(int c = 0; c < col; ++c)
+      m(r, c) = col * c + r;
+
+  // reshape and compare
+  VERIFY_IS_EQUAL((m.reshape< 1, 16>()), Map<MatrixXi>(m.data(),  1, 16));
+  VERIFY_IS_EQUAL((m.reshape< 2,  8>()), Map<MatrixXi>(m.data(),  2,  8));
+  VERIFY_IS_EQUAL((m.reshape< 4,  4>()), Map<MatrixXi>(m.data(),  4,  4));
+  VERIFY_IS_EQUAL((m.reshape< 8,  2>()), Map<MatrixXi>(m.data(),  8,  2));
+  VERIFY_IS_EQUAL((m.reshape<16,  1>()), Map<MatrixXi>(m.data(), 16,  1));
+}
+
+void test_reshape()
+{
+  CALL_SUBTEST(dynamic_reshape_all_size(4, 4));
+  CALL_SUBTEST(static_reshape_all_size());
+}