Function load

include/pybind11/eigen/matrix.h:661–698

    static constexpr bool rowMajor = Type::IsRowMajor;

    bool load(handle src, bool) {
        if (!src) {
            return false;
        }

        auto obj = reinterpret_borrow<object>(src);
        object sparse_module = module_::import("scipy.sparse");
        object matrix_type = sparse_module.attr(rowMajor ? "csr_matrix" : "csc_matrix");

        if (!type::handle_of(obj).is(matrix_type)) {
            try {
                obj = matrix_type(obj);
            } catch (const error_already_set &) {
                return false;
            }
        }

        auto values = array_t<Scalar>((object) obj.attr("data"));
        auto innerIndices = array_t<StorageIndex>((object) obj.attr("indices"));
        auto outerIndices = array_t<StorageIndex>((object) obj.attr("indptr"));
        auto shape = pybind11::tuple((pybind11::object) obj.attr("shape"));
        auto nnz = obj.attr("nnz").cast<Index>();

        if (!values || !innerIndices || !outerIndices) {
            return false;
        }

        value = EigenMapSparseMatrix<Scalar,
                                     Type::Flags &(Eigen::RowMajor | Eigen::ColMajor),
                                     StorageIndex>(shape[0].cast<Index>(),
                                                   shape[1].cast<Index>(),
                                                   std::move(nnz),
                                                   outerIndices.mutable_data(),
                                                   innerIndices.mutable_data(),
                                                   values.mutable_data());

        return true;
    }

    static handle cast(const Type &src, return_value_policy /* policy */, handle /* parent */) {
        const_cast<Type &>(src).makeCompressed();