def test_set_obsm(adata):
    init_hash = joblib.hash(adata)

    dim0_size = np.random.randint(2, adata.shape[0] - 1)
    dim1_size = np.random.randint(1, 99)
    orig_obsm_val = adata.obsm["o"].copy()
    subset_idx = np.random.choice(adata.obs_names, dim0_size, replace=False)

    subset = adata[subset_idx, :]
    assert subset.is_view
    subset.obsm = dict(o=np.ones((dim0_size, dim1_size)))
    assert not subset.is_view
    assert np.all(orig_obsm_val == adata.obsm["o"])  # Checking for mutation
    assert np.all(subset.obsm["o"] == np.ones((dim0_size, dim1_size)))

    subset = adata[subset_idx, :]
    subset_hash = joblib.hash(subset)
    with pytest.raises(ValueError):
        subset.obsm = dict(o=np.ones((dim0_size + 1, dim1_size)))
    with pytest.raises(ValueError):
        subset.varm = dict(o=np.ones((dim0_size - 1, dim1_size)))
    assert subset_hash == joblib.hash(subset)

    # Only modification have been made to a view
    assert init_hash == joblib.hash(adata)
def mmf(f, title='', ax=0):
    """plot magnetomotive force (mmf) of winding"""
    if ax == 0:
        ax = plt.gca()
    if title:
        ax.set_title(title)
    ax.plot(np.array(f['pos'])/np.pi*180, f['mmf'])
    ax.plot(np.array(f['pos_fft'])/np.pi*180, f['mmf_fft'])
    ax.set_xlabel('Position / Deg')

    phi = [f['alfa0']/np.pi*180, f['alfa0']/np.pi*180]
    y = [min(f['mmf_fft']), 1.1*max(f['mmf_fft'])]
    ax.plot(phi, y, '--')
    alfa0 = round(f['alfa0']/np.pi*180, 3)
    ax.text(phi[0]/2, y[0]+0.05, f"{alfa0}°",
            ha="center", va="bottom")
    ax.annotate(f"", xy=(phi[0], y[0]),
                xytext=(0, y[0]), arrowprops=dict(arrowstyle="->"))
    ax.grid()