Add support for RowOrder reshaped

Eigen/src/Core/Reshaped.h

@@ -21,7 +21,7 @@ namespace Eigen {
   * \tparam XprType the type of the expression in which we are taking a reshape
   * \tparam Rows the number of rows of the reshape we are taking at compile time (optional)
   * \tparam Cols the number of columns of the reshape we are taking at compile time (optional)
-  * \tparam Order
+  * \tparam Order can be ColMajor or RowMajor, default is ColMajor.
   *
   * This class represents an expression of either a fixed-size or dynamic-size reshape.
   * It is the return type of DenseBase::reshaped(NRowsType,NColsType) and
@@ -68,9 +68,8 @@ struct traits<Reshaped<XprType, Rows, Cols, Order> > : traits<XprType>
                              : Dynamic,
     OuterStrideAtCompileTime = Dynamic,
 
-    InOrder = Order,
     HasDirectAccess = internal::has_direct_access<XprType>::ret
-                    && (Order==int(AutoOrderValue) || Order==int(XpxStorageOrder))
+                    && (Order==int(XpxStorageOrder))
                     && ((evaluator<XprType>::Flags&LinearAccessBit)==LinearAccessBit),
 
     MaskPacketAccessBit = (InnerSize == Dynamic || (InnerSize % packet_traits<Scalar>::size) == 0)
@@ -324,11 +323,20 @@ struct reshaped_evaluator<ArgType, Rows, Cols, Order, /* HasDirectAccess */ fals
 
   typedef std::pair<Index, Index> RowCol;
 
-  inline RowCol index_remap(Index rowId, Index colId) const {
+  inline RowCol index_remap(Index rowId, Index colId) const
+  {
+    if(Order==ColMajor)
+    {
       const Index nth_elem_idx = colId * m_xpr.rows() + rowId;
-    const Index actual_col = nth_elem_idx / m_xpr.nestedExpression().rows();
+      return RowCol(nth_elem_idx % m_xpr.nestedExpression().rows(),
-    const Index actual_row = nth_elem_idx % m_xpr.nestedExpression().rows();
+                    nth_elem_idx / m_xpr.nestedExpression().rows());
-    return RowCol(actual_row, actual_col);
+    }
+    else
+    {
+      const Index nth_elem_idx = colId + rowId * m_xpr.cols();
+      return RowCol(nth_elem_idx / m_xpr.nestedExpression().cols(),
+                    nth_elem_idx % m_xpr.nestedExpression().cols());
+    }
   }
 
   EIGEN_DEVICE_FUNC

Eigen/src/plugins/ReshapedMethods.h

@@ -40,10 +40,12 @@ reshaped(NRowsType nRows, NColsType nCols)
 
 template<typename NRowsType, typename NColsType, typename OrderType>
 EIGEN_DEVICE_FUNC
-inline Reshaped<Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,OrderType::value>
+inline Reshaped<Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,
+                OrderType::value==AutoOrderValue?Flags&RowMajorBit:OrderType::value>
 reshaped(NRowsType nRows, NColsType nCols, OrderType)
 {
-  return Reshaped<Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,OrderType::value>(
+  return Reshaped<Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,
+                  OrderType::value==AutoOrderValue?Flags&RowMajorBit:OrderType::value>(
             derived(), internal::get_runtime_value(nRows), internal::get_runtime_value(nCols));
 }
 
@@ -59,10 +61,12 @@ reshaped(NRowsType nRows, NColsType nCols) const
 
 template<typename NRowsType, typename NColsType, typename OrderType>
 EIGEN_DEVICE_FUNC
-inline const Reshaped<const Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,OrderType::value>
+inline const Reshaped<const Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,
+                      OrderType::value==AutoOrderValue?Flags&RowMajorBit:OrderType::value>
 reshaped(NRowsType nRows, NColsType nCols, OrderType) const
 {
-  return Reshaped<const Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,OrderType::value>(
+  return Reshaped<const Derived,internal::get_fixed_value<NRowsType>::value,internal::get_fixed_value<NColsType>::value,
+                  OrderType::value==AutoOrderValue?Flags&RowMajorBit:OrderType::value>(
             derived(), internal::get_runtime_value(nRows), internal::get_runtime_value(nCols));
 }
 

test/reshape.cpp

@@ -1,6 +1,7 @@
 // This file is part of Eigen, a lightweight C++ template library
 // for linear algebra.
 //
+// Copyright (C) 2017 Gael Guennebaud <gael.guennebaud@inria.fr>
 // Copyright (C) 2014 yoco <peter.xiau@gmail.com>
 //
 // This Source Code Form is subject to the terms of the Mozilla
@@ -9,15 +10,13 @@
 
 #include "main.h"
 
-using Eigen::Map;
+// just test a 4x4 matrix, enumerate all combination manually
-using Eigen::MatrixXi;
-
-// just test a 4x4 matrix, enumerate all combination manually,
-// so I don't have to do template-meta-programming here.
 template <typename MatType>
-void reshape_all_size(MatType m)
+void reshape4x4(MatType m)
 {
-  typedef Eigen::Map<MatrixXi> MapMat;
+  if((MatType::Flags&RowMajorBit)==0)
+  {
+    typedef Map<MatrixXi> MapMat;
     // dynamic
     VERIFY_IS_EQUAL((m.reshaped( 1, 16)), MapMat(m.data(),  1, 16));
     VERIFY_IS_EQUAL((m.reshaped( 2,  8)), MapMat(m.data(),  2,  8));
@@ -48,6 +47,7 @@ void reshape_all_size(MatType m)
       ),
       MapMat(m.data(), 4,  4)
     );
+  }
 
   VERIFY_IS_EQUAL(m.reshaped( 1, 16).data(), m.data());
   VERIFY_IS_EQUAL(m.reshaped( 1, 16).innerStride(), 1);
@@ -56,23 +56,43 @@ void reshape_all_size(MatType m)
   VERIFY_IS_EQUAL(m.reshaped( 2, 8).innerStride(), 1);
   VERIFY_IS_EQUAL(m.reshaped( 2, 8).outerStride(), 2);
 
-  m.reshaped(2,8,ColOrder);
+  if((MatType::Flags&RowMajorBit)==0)
+  {
+    VERIFY_IS_EQUAL(m.reshaped(2,8,ColOrder),m.reshaped(2,8));
+    VERIFY_IS_EQUAL(m.reshaped(2,8,ColOrder),m.reshaped(2,8,AutoOrder));
+    VERIFY_IS_EQUAL(m.transpose().reshaped(2,8,RowOrder),m.transpose().reshaped(2,8,AutoOrder));
+  }
+  else
+  {
+    VERIFY_IS_EQUAL(m.reshaped(2,8,ColOrder),m.reshaped(2,8));
+    VERIFY_IS_EQUAL(m.reshaped(2,8,RowOrder),m.reshaped(2,8,AutoOrder));
+    VERIFY_IS_EQUAL(m.transpose().reshaped(2,8,ColOrder),m.transpose().reshaped(2,8,AutoOrder));
+    VERIFY_IS_EQUAL(m.transpose().reshaped(2,8),m.transpose().reshaped(2,8,AutoOrder));
+  }
 
-  MatrixXi m28r = m.reshaped(2,8,RowOrder);
+  MatrixXi m28r1 = m.reshaped(2,8,RowOrder);
-  std::cout << m28r << "\n";
+  MatrixXi m28r2 = m.transpose().reshaped(8,2,ColOrder).transpose();
+  VERIFY_IS_EQUAL( m28r1, m28r2);
 }
 
 void test_reshape()
 {
-  Eigen::MatrixXi mx = Eigen::MatrixXi::Random(4, 4);
+  typedef Matrix<int,Dynamic,Dynamic> RowMatrixXi;
-  Eigen::Matrix4i m4 = Eigen::Matrix4i::Random(4, 4);
+  typedef Matrix<int,4,4> RowMatrix4i;
+  MatrixXi mx = MatrixXi::Random(4, 4);
+  Matrix4i m4 = Matrix4i::Random(4, 4);
+  RowMatrixXi rmx = RowMatrixXi::Random(4, 4);
+  RowMatrix4i rm4 = RowMatrix4i::Random(4, 4);
 
   // test dynamic-size matrix
-  CALL_SUBTEST(reshape_all_size(mx));
+  CALL_SUBTEST(reshape4x4(mx));
   // test static-size matrix
-  CALL_SUBTEST(reshape_all_size(m4));
+  CALL_SUBTEST(reshape4x4(m4));
   // test dynamic-size const matrix
-  CALL_SUBTEST(reshape_all_size(static_cast<const Eigen::MatrixXi>(mx)));
+  CALL_SUBTEST(reshape4x4(static_cast<const MatrixXi>(mx)));
   // test static-size const matrix
-  CALL_SUBTEST(reshape_all_size(static_cast<const Eigen::Matrix4i>(m4)));
+  CALL_SUBTEST(reshape4x4(static_cast<const Matrix4i>(m4)));
+
+  CALL_SUBTEST(reshape4x4(rmx));
+  CALL_SUBTEST(reshape4x4(rm4));
 }