def test_shift_time_evoked():
    tempdir = _TempDir()
    # Shift backward
    ave = read_evokeds(fname, 0)
    ave.shift_time(-0.1, relative=True)
    write_evokeds(op.join(tempdir, 'evoked-ave.fif'), ave)

    # Shift forward twice the amount
    ave_bshift = read_evokeds(op.join(tempdir, 'evoked-ave.fif'), 0)
    ave_bshift.shift_time(0.2, relative=True)
    write_evokeds(op.join(tempdir, 'evoked-ave.fif'), ave_bshift)

    # Shift backward again
    ave_fshift = read_evokeds(op.join(tempdir, 'evoked-ave.fif'), 0)
    ave_fshift.shift_time(-0.1, relative=True)
    write_evokeds(op.join(tempdir, 'evoked-ave.fif'), ave_fshift)

    ave_normal = read_evokeds(fname, 0)
    ave_relative = read_evokeds(op.join(tempdir, 'evoked-ave.fif'), 0)

    assert_true(np.allclose(ave_normal.data, ave_relative.data,
                            atol=1e-16, rtol=1e-3))
    assert_array_almost_equal(ave_normal.times, ave_relative.times, 10)

    assert_equal(ave_normal.last, ave_relative.last)
    assert_equal(ave_normal.first, ave_relative.first)

    # Absolute time shift
    ave = read_evokeds(fname, 0)
    ave.shift_time(-0.3, relative=False)
    write_evokeds(op.join(tempdir, 'evoked-ave.fif'), ave)

    ave_absolute = read_evokeds(op.join(tempdir, 'evoked-ave.fif'), 0)

    assert_true(np.allclose(ave_normal.data, ave_absolute.data,
                            atol=1e-16, rtol=1e-3))
    assert_equal(ave_absolute.first, int(-0.3 * ave.info['sfreq']))
Test for shifting of time scale
dataset/ETHPy150Open mne-tools/mne-python/mne/tests/test_evoked.py/test_shift_time_evoked