Method test_trace

numpy/ma/tests/test_core.py:4229–4242

(self)

                            [[-0.5, 0.5, mval], [-1.0, mval, 1.0]])

    def test_trace(self):
        # Tests trace on MaskedArrays.
        _, X, _, _, _, mX, _, _, _, _ = self._create_data()
        mXdiag = mX.diagonal()
        assert_equal(mX.trace(), mX.diagonal().compressed().sum())
        assert_almost_equal(mX.trace(),
                            X.trace() - sum(mXdiag.mask * X.diagonal(),
                                            axis=0))
        assert_equal(np.trace(mX), mX.trace())

        # gh-5560
        arr = np.arange(2 * 4 * 4).reshape(2, 4, 4)
        m_arr = np.ma.masked_array(arr, False)
        assert_equal(arr.trace(axis1=1, axis2=2), m_arr.trace(axis1=1, axis2=2))

    def test_dot(self):
        # Tests dot on MaskedArrays.