Function cast

include/pybind11/eigen/matrix.h:700–714

    }

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

        object matrix_type
            = module_::import("scipy.sparse").attr(rowMajor ? "csr_matrix" : "csc_matrix");

        array data(src.nonZeros(), src.valuePtr());
        array outerIndices((rowMajor ? src.rows() : src.cols()) + 1, src.outerIndexPtr());
        array innerIndices(src.nonZeros(), src.innerIndexPtr());

        return matrix_type(pybind11::make_tuple(
                               std::move(data), std::move(innerIndices), std::move(outerIndices)),
                           pybind11::make_tuple(src.rows(), src.cols()))
            .release();
    }

    PYBIND11_TYPE_CASTER(Type,
                         const_name<(Type::IsRowMajor) != 0>("scipy.sparse.csr_matrix[",