Merge pull request #267 from bennorth/non-contiguous-arrays

Non-contiguous arrays

example/eigen.cpp

@@ -10,6 +10,19 @@
 #include "example.h"
 #include <pybind11/eigen.h>
 
+Eigen::VectorXf double_col(const Eigen::VectorXf& x)
+{ return 2.0f * x; }
+
+Eigen::RowVectorXf double_row(const Eigen::RowVectorXf& x)
+{ return 2.0f * x; }
+
+Eigen::MatrixXf double_mat_cm(const Eigen::MatrixXf& x)
+{ return 2.0f * x; }
+
+typedef Eigen::Matrix<float, Eigen::Dynamic, Eigen::Dynamic, Eigen::RowMajor> MatrixXfRowMajor;
+MatrixXfRowMajor double_mat_rm(const MatrixXfRowMajor& x)
+{ return 2.0f * x; }
+
 void init_eigen(py::module &m) {
     typedef Eigen::Matrix<float, 5, 6, Eigen::RowMajor> FixedMatrixR;
     typedef Eigen::Matrix<float, 5, 6> FixedMatrixC;
@@ -23,6 +36,11 @@ void init_eigen(py::module &m) {
     mat << 0, 3, 0, 0, 0, 11, 22, 0, 0, 0, 17, 11, 7, 5, 0, 1, 0, 11, 0,
         0, 0, 0, 0, 11, 0, 0, 14, 0, 8, 11;
 
+    m.def("double_col", &double_col);
+    m.def("double_row", &double_row);
+    m.def("double_mat_cm", &double_mat_cm);
+    m.def("double_mat_rm", &double_mat_rm);
+
     m.def("fixed_r", [mat]() -> FixedMatrixR { 
         return FixedMatrixR(mat);
     });

example/eigen.py

@@ -9,6 +9,8 @@ from example import dense_r, dense_c
 from example import dense_passthrough_r, dense_passthrough_c
 from example import sparse_r, sparse_c
 from example import sparse_passthrough_r, sparse_passthrough_c
+from example import double_row, double_col
+from example import double_mat_cm, double_mat_rm
 import numpy as np
 
 ref = np.array(
@@ -42,3 +44,22 @@ print("pt_r(sparse_r) = %s" % check(sparse_passthrough_r(sparse_r())))
 print("pt_c(sparse_c) = %s" % check(sparse_passthrough_c(sparse_c())))
 print("pt_r(sparse_c) = %s" % check(sparse_passthrough_r(sparse_c())))
 print("pt_c(sparse_r) = %s" % check(sparse_passthrough_c(sparse_r())))
+
+def check_got_vs_ref(got_x, ref_x):
+    return 'OK' if np.array_equal(got_x, ref_x) else 'NOT OK'
+
+counting_mat = np.arange(9.0, dtype=np.float32).reshape((3, 3))
+first_row = counting_mat[0, :]
+first_col = counting_mat[:, 0]
+
+print("double_row(first_row) = %s" % check_got_vs_ref(double_row(first_row), 2.0 * first_row))
+print("double_col(first_row) = %s" % check_got_vs_ref(double_col(first_row), 2.0 * first_row))
+print("double_row(first_col) = %s" % check_got_vs_ref(double_row(first_col), 2.0 * first_col))
+print("double_col(first_col) = %s" % check_got_vs_ref(double_col(first_col), 2.0 * first_col))
+
+counting_3d = np.arange(27.0, dtype=np.float32).reshape((3, 3, 3))
+slices = [counting_3d[0, :, :], counting_3d[:, 0, :], counting_3d[:, :, 0]]
+
+for slice_idx, ref_mat in enumerate(slices):
+    print("double_mat_cm(%d) = %s" % (slice_idx, check_got_vs_ref(double_mat_cm(ref_mat), 2.0 * ref_mat)))
+    print("double_mat_rm(%d) = %s" % (slice_idx, check_got_vs_ref(double_mat_rm(ref_mat), 2.0 * ref_mat)))

example/eigen.ref

@@ -16,3 +16,13 @@ pt_r(sparse_r) = OK
 pt_c(sparse_c) = OK
 pt_r(sparse_c) = OK
 pt_c(sparse_r) = OK
+double_row(first_row) = OK
+double_col(first_row) = OK
+double_row(first_col) = OK
+double_col(first_col) = OK
+double_mat_cm(0) = OK
+double_mat_rm(0) = OK
+double_mat_cm(1) = OK
+double_mat_rm(1) = OK
+double_mat_cm(2) = OK
+double_mat_rm(2) = OK

include/pybind11/eigen.h

@@ -61,7 +61,7 @@ struct type_caster<Type, typename std::enable_if<is_eigen_dense<Type>::value>::t
 
         buffer_info info = buffer.request();
         if (info.ndim == 1) {
-            typedef Eigen::Stride<Eigen::Dynamic, 0> Strides;
+            typedef Eigen::InnerStride<> Strides;
             if (!isVector &&
                 !(Type::RowsAtCompileTime == Eigen::Dynamic &&
                   Type::ColsAtCompileTime == Eigen::Dynamic))
@@ -71,10 +71,13 @@ struct type_caster<Type, typename std::enable_if<is_eigen_dense<Type>::value>::t
                 info.shape[0] != (size_t) Type::SizeAtCompileTime)
                 return false;
 
-            auto strides = Strides(info.strides[0] / sizeof(Scalar), 0);
+            auto strides = Strides(info.strides[0] / sizeof(Scalar));
+
+            Strides::Index n_elts = info.shape[0];
+            Strides::Index unity = 1;
 
             value = Eigen::Map<Type, 0, Strides>(
-                (Scalar *) info.ptr, typename Strides::Index(info.shape[0]), 1, strides);
+                (Scalar *) info.ptr, rowMajor ? unity : n_elts, rowMajor ? n_elts : unity, strides);
         } else if (info.ndim == 2) {
             typedef Eigen::Stride<Eigen::Dynamic, Eigen::Dynamic> Strides;