make get_array compatible with Eigen version <= 3.3.7

Cryoris · Cryoris · commit 03ba62e80f33 · 2019-08-29T16:43:02.000+02:00
diff --git a/matplotlibcpp.h b/matplotlibcpp.h
@@ -362,14 +362,16 @@ template <> struct select_npy_type<uint64_t> {
 
 // TODO change to Vector template so useable for Eigen vectors,
 // should be enough since it also provides the end and begin methods
-template <typename Numeric> PyObject *get_array(const std::vector<Numeric> &v) {
+template <typename Vector> PyObject *get_array(const Vector &v) {
   detail::_interpreter::get(); // interpreter needs to be initialized for the
                                // numpy commands to work
   NPY_TYPES type = select_npy_type<Numeric>::type;
   if (type == NPY_NOTYPE) {
     std::vector<double> vd(v.size());
     npy_intp vsize = v.size();
-    std::copy(v.begin(), v.end(), vd.begin());
+    // Eigen Vectors do not support begin/end() in the currently stable version
+    // this can be changed once Eigen 3.4. is released
+    std::copy(v.data(), v.data() + v.size(), vd.begin());
     PyObject *varray =
         PyArray_SimpleNewFromData(1, &vsize, NPY_DOUBLE, (void *)(vd.data()));
     return varray;
@@ -389,7 +391,9 @@ template <typename Vector> PyObject *get_array(const Vector &v) {
   if (type == NPY_NOTYPE) {
     std::vector<double> vd(v.size());
     npy_intp vsize = v.size();
-    std::copy(v.begin(), v.end(), vd.begin());
+    // Eigen Vectors do not support begin/end() in the currently stable version
+    // this can be changed once Eigen 3.4. is released
+    std::copy(v.data(), v.data() + v.size(), vd.begin());
     PyObject *varray =
         PyArray_SimpleNewFromData(1, &vsize, NPY_DOUBLE, (void *)(vd.data()));
     return varray;
