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diff --git a/.venv/lib/python3.12/site-packages/networkx/drawing/tests/test_pylab.py b/.venv/lib/python3.12/site-packages/networkx/drawing/tests/test_pylab.py new file mode 100644 index 00000000..c9931db8 --- /dev/null +++ b/.venv/lib/python3.12/site-packages/networkx/drawing/tests/test_pylab.py @@ -0,0 +1,1029 @@ +"""Unit tests for matplotlib drawing functions.""" + +import itertools +import os +import warnings + +import pytest + +mpl = pytest.importorskip("matplotlib") +np = pytest.importorskip("numpy") +mpl.use("PS") +plt = pytest.importorskip("matplotlib.pyplot") +plt.rcParams["text.usetex"] = False + + +import networkx as nx + +barbell = nx.barbell_graph(4, 6) + + +def test_draw(): + try: + functions = [ + nx.draw_circular, + nx.draw_kamada_kawai, + nx.draw_planar, + nx.draw_random, + nx.draw_spectral, + nx.draw_spring, + nx.draw_shell, + ] + options = [{"node_color": "black", "node_size": 100, "width": 3}] + for function, option in itertools.product(functions, options): + function(barbell, **option) + plt.savefig("test.ps") + except ModuleNotFoundError: # draw_kamada_kawai requires scipy + pass + finally: + try: + os.unlink("test.ps") + except OSError: + pass + + +def test_draw_shell_nlist(): + try: + nlist = [list(range(4)), list(range(4, 10)), list(range(10, 14))] + nx.draw_shell(barbell, nlist=nlist) + plt.savefig("test.ps") + finally: + try: + os.unlink("test.ps") + except OSError: + pass + + +def test_edge_colormap(): + colors = range(barbell.number_of_edges()) + nx.draw_spring( + barbell, edge_color=colors, width=4, edge_cmap=plt.cm.Blues, with_labels=True + ) + # plt.show() + + +def test_arrows(): + nx.draw_spring(barbell.to_directed()) + # plt.show() + + +@pytest.mark.parametrize( + ("edge_color", "expected"), + ( + (None, "black"), # Default + ("r", "red"), # Non-default color string + (["r"], "red"), # Single non-default color in a list + ((1.0, 1.0, 0.0), "yellow"), # single color as rgb tuple + ([(1.0, 1.0, 0.0)], "yellow"), # single color as rgb tuple in list + ((0, 1, 0, 1), "lime"), # single color as rgba tuple + ([(0, 1, 0, 1)], "lime"), # single color as rgba tuple in list + ("#0000ff", "blue"), # single color hex code + (["#0000ff"], "blue"), # hex code in list + ), +) +@pytest.mark.parametrize("edgelist", (None, [(0, 1)])) +def test_single_edge_color_undirected(edge_color, expected, edgelist): + """Tests ways of specifying all edges have a single color for edges + drawn with a LineCollection""" + + G = nx.path_graph(3) + drawn_edges = nx.draw_networkx_edges( + G, pos=nx.random_layout(G), edgelist=edgelist, edge_color=edge_color + ) + assert mpl.colors.same_color(drawn_edges.get_color(), expected) + + +@pytest.mark.parametrize( + ("edge_color", "expected"), + ( + (None, "black"), # Default + ("r", "red"), # Non-default color string + (["r"], "red"), # Single non-default color in a list + ((1.0, 1.0, 0.0), "yellow"), # single color as rgb tuple + ([(1.0, 1.0, 0.0)], "yellow"), # single color as rgb tuple in list + ((0, 1, 0, 1), "lime"), # single color as rgba tuple + ([(0, 1, 0, 1)], "lime"), # single color as rgba tuple in list + ("#0000ff", "blue"), # single color hex code + (["#0000ff"], "blue"), # hex code in list + ), +) +@pytest.mark.parametrize("edgelist", (None, [(0, 1)])) +def test_single_edge_color_directed(edge_color, expected, edgelist): + """Tests ways of specifying all edges have a single color for edges drawn + with FancyArrowPatches""" + + G = nx.path_graph(3, create_using=nx.DiGraph) + drawn_edges = nx.draw_networkx_edges( + G, pos=nx.random_layout(G), edgelist=edgelist, edge_color=edge_color + ) + for fap in drawn_edges: + assert mpl.colors.same_color(fap.get_edgecolor(), expected) + + +def test_edge_color_tuple_interpretation(): + """If edge_color is a sequence with the same length as edgelist, then each + value in edge_color is mapped onto each edge via colormap.""" + G = nx.path_graph(6, create_using=nx.DiGraph) + pos = {n: (n, n) for n in range(len(G))} + + # num edges != 3 or 4 --> edge_color interpreted as rgb(a) + for ec in ((0, 0, 1), (0, 0, 1, 1)): + # More than 4 edges + drawn_edges = nx.draw_networkx_edges(G, pos, edge_color=ec) + for fap in drawn_edges: + assert mpl.colors.same_color(fap.get_edgecolor(), ec) + # Fewer than 3 edges + drawn_edges = nx.draw_networkx_edges( + G, pos, edgelist=[(0, 1), (1, 2)], edge_color=ec + ) + for fap in drawn_edges: + assert mpl.colors.same_color(fap.get_edgecolor(), ec) + + # num edges == 3, len(edge_color) == 4: interpreted as rgba + drawn_edges = nx.draw_networkx_edges( + G, pos, edgelist=[(0, 1), (1, 2), (2, 3)], edge_color=(0, 0, 1, 1) + ) + for fap in drawn_edges: + assert mpl.colors.same_color(fap.get_edgecolor(), "blue") + + # num edges == 4, len(edge_color) == 3: interpreted as rgb + drawn_edges = nx.draw_networkx_edges( + G, pos, edgelist=[(0, 1), (1, 2), (2, 3), (3, 4)], edge_color=(0, 0, 1) + ) + for fap in drawn_edges: + assert mpl.colors.same_color(fap.get_edgecolor(), "blue") + + # num edges == len(edge_color) == 3: interpreted with cmap, *not* as rgb + drawn_edges = nx.draw_networkx_edges( + G, pos, edgelist=[(0, 1), (1, 2), (2, 3)], edge_color=(0, 0, 1) + ) + assert mpl.colors.same_color( + drawn_edges[0].get_edgecolor(), drawn_edges[1].get_edgecolor() + ) + for fap in drawn_edges: + assert not mpl.colors.same_color(fap.get_edgecolor(), "blue") + + # num edges == len(edge_color) == 4: interpreted with cmap, *not* as rgba + drawn_edges = nx.draw_networkx_edges( + G, pos, edgelist=[(0, 1), (1, 2), (2, 3), (3, 4)], edge_color=(0, 0, 1, 1) + ) + assert mpl.colors.same_color( + drawn_edges[0].get_edgecolor(), drawn_edges[1].get_edgecolor() + ) + assert mpl.colors.same_color( + drawn_edges[2].get_edgecolor(), drawn_edges[3].get_edgecolor() + ) + for fap in drawn_edges: + assert not mpl.colors.same_color(fap.get_edgecolor(), "blue") + + +def test_fewer_edge_colors_than_num_edges_directed(): + """Test that the edge colors are cycled when there are fewer specified + colors than edges.""" + G = barbell.to_directed() + pos = nx.random_layout(barbell) + edgecolors = ("r", "g", "b") + drawn_edges = nx.draw_networkx_edges(G, pos, edge_color=edgecolors) + for fap, expected in zip(drawn_edges, itertools.cycle(edgecolors)): + assert mpl.colors.same_color(fap.get_edgecolor(), expected) + + +def test_more_edge_colors_than_num_edges_directed(): + """Test that extra edge colors are ignored when there are more specified + colors than edges.""" + G = nx.path_graph(4, create_using=nx.DiGraph) # 3 edges + pos = nx.random_layout(barbell) + edgecolors = ("r", "g", "b", "c") # 4 edge colors + drawn_edges = nx.draw_networkx_edges(G, pos, edge_color=edgecolors) + for fap, expected in zip(drawn_edges, edgecolors[:-1]): + assert mpl.colors.same_color(fap.get_edgecolor(), expected) + + +def test_edge_color_string_with_global_alpha_undirected(): + edge_collection = nx.draw_networkx_edges( + barbell, + pos=nx.random_layout(barbell), + edgelist=[(0, 1), (1, 2)], + edge_color="purple", + alpha=0.2, + ) + ec = edge_collection.get_color().squeeze() # as rgba tuple + assert len(edge_collection.get_paths()) == 2 + assert mpl.colors.same_color(ec[:-1], "purple") + assert ec[-1] == 0.2 + + +def test_edge_color_string_with_global_alpha_directed(): + drawn_edges = nx.draw_networkx_edges( + barbell.to_directed(), + pos=nx.random_layout(barbell), + edgelist=[(0, 1), (1, 2)], + edge_color="purple", + alpha=0.2, + ) + assert len(drawn_edges) == 2 + for fap in drawn_edges: + ec = fap.get_edgecolor() # As rgba tuple + assert mpl.colors.same_color(ec[:-1], "purple") + assert ec[-1] == 0.2 + + +@pytest.mark.parametrize("graph_type", (nx.Graph, nx.DiGraph)) +def test_edge_width_default_value(graph_type): + """Test the default linewidth for edges drawn either via LineCollection or + FancyArrowPatches.""" + G = nx.path_graph(2, create_using=graph_type) + pos = {n: (n, n) for n in range(len(G))} + drawn_edges = nx.draw_networkx_edges(G, pos) + if isinstance(drawn_edges, list): # directed case: list of FancyArrowPatch + drawn_edges = drawn_edges[0] + assert drawn_edges.get_linewidth() == 1 + + +@pytest.mark.parametrize( + ("edgewidth", "expected"), + ( + (3, 3), # single-value, non-default + ([3], 3), # Single value as a list + ), +) +def test_edge_width_single_value_undirected(edgewidth, expected): + G = nx.path_graph(4) + pos = {n: (n, n) for n in range(len(G))} + drawn_edges = nx.draw_networkx_edges(G, pos, width=edgewidth) + assert len(drawn_edges.get_paths()) == 3 + assert drawn_edges.get_linewidth() == expected + + +@pytest.mark.parametrize( + ("edgewidth", "expected"), + ( + (3, 3), # single-value, non-default + ([3], 3), # Single value as a list + ), +) +def test_edge_width_single_value_directed(edgewidth, expected): + G = nx.path_graph(4, create_using=nx.DiGraph) + pos = {n: (n, n) for n in range(len(G))} + drawn_edges = nx.draw_networkx_edges(G, pos, width=edgewidth) + assert len(drawn_edges) == 3 + for fap in drawn_edges: + assert fap.get_linewidth() == expected + + +@pytest.mark.parametrize( + "edgelist", + ( + [(0, 1), (1, 2), (2, 3)], # one width specification per edge + None, # fewer widths than edges - widths cycle + [(0, 1), (1, 2)], # More widths than edges - unused widths ignored + ), +) +def test_edge_width_sequence(edgelist): + G = barbell.to_directed() + pos = nx.random_layout(G) + widths = (0.5, 2.0, 12.0) + drawn_edges = nx.draw_networkx_edges(G, pos, edgelist=edgelist, width=widths) + for fap, expected_width in zip(drawn_edges, itertools.cycle(widths)): + assert fap.get_linewidth() == expected_width + + +def test_edge_color_with_edge_vmin_vmax(): + """Test that edge_vmin and edge_vmax properly set the dynamic range of the + color map when num edges == len(edge_colors).""" + G = nx.path_graph(3, create_using=nx.DiGraph) + pos = nx.random_layout(G) + # Extract colors from the original (unscaled) colormap + drawn_edges = nx.draw_networkx_edges(G, pos, edge_color=[0, 1.0]) + orig_colors = [e.get_edgecolor() for e in drawn_edges] + # Colors from scaled colormap + drawn_edges = nx.draw_networkx_edges( + G, pos, edge_color=[0.2, 0.8], edge_vmin=0.2, edge_vmax=0.8 + ) + scaled_colors = [e.get_edgecolor() for e in drawn_edges] + assert mpl.colors.same_color(orig_colors, scaled_colors) + + +def test_directed_edges_linestyle_default(): + """Test default linestyle for edges drawn with FancyArrowPatches.""" + G = nx.path_graph(4, create_using=nx.DiGraph) # Graph with 3 edges + pos = {n: (n, n) for n in range(len(G))} + + # edge with default style + drawn_edges = nx.draw_networkx_edges(G, pos) + assert len(drawn_edges) == 3 + for fap in drawn_edges: + assert fap.get_linestyle() == "solid" + + +@pytest.mark.parametrize( + "style", + ( + "dashed", # edge with string style + "--", # edge with simplified string style + (1, (1, 1)), # edge with (offset, onoffseq) style + ), +) +def test_directed_edges_linestyle_single_value(style): + """Tests support for specifying linestyles with a single value to be applied to + all edges in ``draw_networkx_edges`` for FancyArrowPatch outputs + (e.g. directed edges).""" + + G = nx.path_graph(4, create_using=nx.DiGraph) # Graph with 3 edges + pos = {n: (n, n) for n in range(len(G))} + + drawn_edges = nx.draw_networkx_edges(G, pos, style=style) + assert len(drawn_edges) == 3 + for fap in drawn_edges: + assert fap.get_linestyle() == style + + +@pytest.mark.parametrize( + "style_seq", + ( + ["dashed"], # edge with string style in list + ["--"], # edge with simplified string style in list + [(1, (1, 1))], # edge with (offset, onoffseq) style in list + ["--", "-", ":"], # edges with styles for each edge + ["--", "-"], # edges with fewer styles than edges (styles cycle) + ["--", "-", ":", "-."], # edges with more styles than edges (extra unused) + ), +) +def test_directed_edges_linestyle_sequence(style_seq): + """Tests support for specifying linestyles with sequences in + ``draw_networkx_edges`` for FancyArrowPatch outputs (e.g. directed edges).""" + + G = nx.path_graph(4, create_using=nx.DiGraph) # Graph with 3 edges + pos = {n: (n, n) for n in range(len(G))} + + drawn_edges = nx.draw_networkx_edges(G, pos, style=style_seq) + assert len(drawn_edges) == 3 + for fap, style in zip(drawn_edges, itertools.cycle(style_seq)): + assert fap.get_linestyle() == style + + +def test_return_types(): + from matplotlib.collections import LineCollection, PathCollection + from matplotlib.patches import FancyArrowPatch + + G = nx.cubical_graph(nx.Graph) + dG = nx.cubical_graph(nx.DiGraph) + pos = nx.spring_layout(G) + dpos = nx.spring_layout(dG) + # nodes + nodes = nx.draw_networkx_nodes(G, pos) + assert isinstance(nodes, PathCollection) + # edges + edges = nx.draw_networkx_edges(dG, dpos, arrows=True) + assert isinstance(edges, list) + if len(edges) > 0: + assert isinstance(edges[0], FancyArrowPatch) + edges = nx.draw_networkx_edges(dG, dpos, arrows=False) + assert isinstance(edges, LineCollection) + edges = nx.draw_networkx_edges(G, dpos, arrows=None) + assert isinstance(edges, LineCollection) + edges = nx.draw_networkx_edges(dG, pos, arrows=None) + assert isinstance(edges, list) + if len(edges) > 0: + assert isinstance(edges[0], FancyArrowPatch) + + +def test_labels_and_colors(): + G = nx.cubical_graph() + pos = nx.spring_layout(G) # positions for all nodes + # nodes + nx.draw_networkx_nodes( + G, pos, nodelist=[0, 1, 2, 3], node_color="r", node_size=500, alpha=0.75 + ) + nx.draw_networkx_nodes( + G, + pos, + nodelist=[4, 5, 6, 7], + node_color="b", + node_size=500, + alpha=[0.25, 0.5, 0.75, 1.0], + ) + # edges + nx.draw_networkx_edges(G, pos, width=1.0, alpha=0.5) + nx.draw_networkx_edges( + G, + pos, + edgelist=[(0, 1), (1, 2), (2, 3), (3, 0)], + width=8, + alpha=0.5, + edge_color="r", + ) + nx.draw_networkx_edges( + G, + pos, + edgelist=[(4, 5), (5, 6), (6, 7), (7, 4)], + width=8, + alpha=0.5, + edge_color="b", + ) + nx.draw_networkx_edges( + G, + pos, + edgelist=[(4, 5), (5, 6), (6, 7), (7, 4)], + arrows=True, + min_source_margin=0.5, + min_target_margin=0.75, + width=8, + edge_color="b", + ) + # some math labels + labels = {} + labels[0] = r"$a$" + labels[1] = r"$b$" + labels[2] = r"$c$" + labels[3] = r"$d$" + labels[4] = r"$\alpha$" + labels[5] = r"$\beta$" + labels[6] = r"$\gamma$" + labels[7] = r"$\delta$" + colors = {n: "k" if n % 2 == 0 else "r" for n in range(8)} + nx.draw_networkx_labels(G, pos, labels, font_size=16) + nx.draw_networkx_labels(G, pos, labels, font_size=16, font_color=colors) + nx.draw_networkx_edge_labels(G, pos, edge_labels=None, rotate=False) + nx.draw_networkx_edge_labels(G, pos, edge_labels={(4, 5): "4-5"}) + # plt.show() + + +@pytest.mark.mpl_image_compare +def test_house_with_colors(): + G = nx.house_graph() + # explicitly set positions + fig, ax = plt.subplots() + pos = {0: (0, 0), 1: (1, 0), 2: (0, 1), 3: (1, 1), 4: (0.5, 2.0)} + + # Plot nodes with different properties for the "wall" and "roof" nodes + nx.draw_networkx_nodes( + G, + pos, + node_size=3000, + nodelist=[0, 1, 2, 3], + node_color="tab:blue", + ) + nx.draw_networkx_nodes( + G, pos, node_size=2000, nodelist=[4], node_color="tab:orange" + ) + nx.draw_networkx_edges(G, pos, alpha=0.5, width=6) + # Customize axes + ax.margins(0.11) + plt.tight_layout() + plt.axis("off") + return fig + + +def test_axes(): + fig, ax = plt.subplots() + nx.draw(barbell, ax=ax) + nx.draw_networkx_edge_labels(barbell, nx.circular_layout(barbell), ax=ax) + + +def test_empty_graph(): + G = nx.Graph() + nx.draw(G) + + +def test_draw_empty_nodes_return_values(): + # See Issue #3833 + import matplotlib.collections # call as mpl.collections + + G = nx.Graph([(1, 2), (2, 3)]) + DG = nx.DiGraph([(1, 2), (2, 3)]) + pos = nx.circular_layout(G) + assert isinstance( + nx.draw_networkx_nodes(G, pos, nodelist=[]), mpl.collections.PathCollection + ) + assert isinstance( + nx.draw_networkx_nodes(DG, pos, nodelist=[]), mpl.collections.PathCollection + ) + + # drawing empty edges used to return an empty LineCollection or empty list. + # Now it is always an empty list (because edges are now lists of FancyArrows) + assert nx.draw_networkx_edges(G, pos, edgelist=[], arrows=True) == [] + assert nx.draw_networkx_edges(G, pos, edgelist=[], arrows=False) == [] + assert nx.draw_networkx_edges(DG, pos, edgelist=[], arrows=False) == [] + assert nx.draw_networkx_edges(DG, pos, edgelist=[], arrows=True) == [] + + +def test_multigraph_edgelist_tuples(): + # See Issue #3295 + G = nx.path_graph(3, create_using=nx.MultiDiGraph) + nx.draw_networkx(G, edgelist=[(0, 1, 0)]) + nx.draw_networkx(G, edgelist=[(0, 1, 0)], node_size=[10, 20, 0]) + + +def test_alpha_iter(): + pos = nx.random_layout(barbell) + fig = plt.figure() + # with fewer alpha elements than nodes + fig.add_subplot(131) # Each test in a new axis object + nx.draw_networkx_nodes(barbell, pos, alpha=[0.1, 0.2]) + # with equal alpha elements and nodes + num_nodes = len(barbell.nodes) + alpha = [x / num_nodes for x in range(num_nodes)] + colors = range(num_nodes) + fig.add_subplot(132) + nx.draw_networkx_nodes(barbell, pos, node_color=colors, alpha=alpha) + # with more alpha elements than nodes + alpha.append(1) + fig.add_subplot(133) + nx.draw_networkx_nodes(barbell, pos, alpha=alpha) + + +def test_multiple_node_shapes(): + G = nx.path_graph(4) + ax = plt.figure().add_subplot(111) + nx.draw(G, node_shape=["o", "h", "s", "^"], ax=ax) + scatters = [ + s for s in ax.get_children() if isinstance(s, mpl.collections.PathCollection) + ] + assert len(scatters) == 4 + + +def test_individualized_font_attributes(): + G = nx.karate_club_graph() + ax = plt.figure().add_subplot(111) + nx.draw( + G, + ax=ax, + font_color={n: "k" if n % 2 else "r" for n in G.nodes()}, + font_size={n: int(n / (34 / 15) + 5) for n in G.nodes()}, + ) + for n, t in zip( + G.nodes(), + [ + t + for t in ax.get_children() + if isinstance(t, mpl.text.Text) and len(t.get_text()) > 0 + ], + ): + expected = "black" if n % 2 else "red" + + assert mpl.colors.same_color(t.get_color(), expected) + assert int(n / (34 / 15) + 5) == t.get_size() + + +def test_individualized_edge_attributes(): + G = nx.karate_club_graph() + ax = plt.figure().add_subplot(111) + arrowstyles = ["-|>" if (u + v) % 2 == 0 else "-[" for u, v in G.edges()] + arrowsizes = [10 * (u % 2 + v % 2) + 10 for u, v in G.edges()] + nx.draw(G, ax=ax, arrows=True, arrowstyle=arrowstyles, arrowsize=arrowsizes) + arrows = [ + f for f in ax.get_children() if isinstance(f, mpl.patches.FancyArrowPatch) + ] + for e, a in zip(G.edges(), arrows): + assert a.get_mutation_scale() == 10 * (e[0] % 2 + e[1] % 2) + 10 + expected = ( + mpl.patches.ArrowStyle.BracketB + if sum(e) % 2 + else mpl.patches.ArrowStyle.CurveFilledB + ) + assert isinstance(a.get_arrowstyle(), expected) + + +def test_error_invalid_kwds(): + with pytest.raises(ValueError, match="Received invalid argument"): + nx.draw(barbell, foo="bar") + + +def test_draw_networkx_arrowsize_incorrect_size(): + G = nx.DiGraph([(0, 1), (0, 2), (0, 3), (1, 3)]) + arrowsize = [1, 2, 3] + with pytest.raises( + ValueError, match="arrowsize should have the same length as edgelist" + ): + nx.draw(G, arrowsize=arrowsize) + + +@pytest.mark.parametrize("arrowsize", (30, [10, 20, 30])) +def test_draw_edges_arrowsize(arrowsize): + G = nx.DiGraph([(0, 1), (0, 2), (1, 2)]) + pos = {0: (0, 0), 1: (0, 1), 2: (1, 0)} + edges = nx.draw_networkx_edges(G, pos=pos, arrowsize=arrowsize) + + arrowsize = itertools.repeat(arrowsize) if isinstance(arrowsize, int) else arrowsize + + for fap, expected in zip(edges, arrowsize): + assert isinstance(fap, mpl.patches.FancyArrowPatch) + assert fap.get_mutation_scale() == expected + + +@pytest.mark.parametrize("arrowstyle", ("-|>", ["-|>", "-[", "<|-|>"])) +def test_draw_edges_arrowstyle(arrowstyle): + G = nx.DiGraph([(0, 1), (0, 2), (1, 2)]) + pos = {0: (0, 0), 1: (0, 1), 2: (1, 0)} + edges = nx.draw_networkx_edges(G, pos=pos, arrowstyle=arrowstyle) + + arrowstyle = ( + itertools.repeat(arrowstyle) if isinstance(arrowstyle, str) else arrowstyle + ) + + arrow_objects = { + "-|>": mpl.patches.ArrowStyle.CurveFilledB, + "-[": mpl.patches.ArrowStyle.BracketB, + "<|-|>": mpl.patches.ArrowStyle.CurveFilledAB, + } + + for fap, expected in zip(edges, arrowstyle): + assert isinstance(fap, mpl.patches.FancyArrowPatch) + assert isinstance(fap.get_arrowstyle(), arrow_objects[expected]) + + +def test_np_edgelist(): + # see issue #4129 + nx.draw_networkx(barbell, edgelist=np.array([(0, 2), (0, 3)])) + + +def test_draw_nodes_missing_node_from_position(): + G = nx.path_graph(3) + pos = {0: (0, 0), 1: (1, 1)} # No position for node 2 + with pytest.raises(nx.NetworkXError, match="has no position"): + nx.draw_networkx_nodes(G, pos) + + +# NOTE: parametrizing on marker to test both branches of internal +# nx.draw_networkx_edges.to_marker_edge function +@pytest.mark.parametrize("node_shape", ("o", "s")) +def test_draw_edges_min_source_target_margins(node_shape): + """Test that there is a wider gap between the node and the start of an + incident edge when min_source_margin is specified. + + This test checks that the use of min_{source/target}_margin kwargs result + in shorter (more padding) between the edges and source and target nodes. + As a crude visual example, let 's' and 't' represent source and target + nodes, respectively: + + Default: + s-----------------------------t + + With margins: + s ----------------------- t + + """ + # Create a single axis object to get consistent pixel coords across + # multiple draws + fig, ax = plt.subplots() + G = nx.DiGraph([(0, 1)]) + pos = {0: (0, 0), 1: (1, 0)} # horizontal layout + # Get leftmost and rightmost points of the FancyArrowPatch object + # representing the edge between nodes 0 and 1 (in pixel coordinates) + default_patch = nx.draw_networkx_edges(G, pos, ax=ax, node_shape=node_shape)[0] + default_extent = default_patch.get_extents().corners()[::2, 0] + # Now, do the same but with "padding" for the source and target via the + # min_{source/target}_margin kwargs + padded_patch = nx.draw_networkx_edges( + G, + pos, + ax=ax, + node_shape=node_shape, + min_source_margin=100, + min_target_margin=100, + )[0] + padded_extent = padded_patch.get_extents().corners()[::2, 0] + + # With padding, the left-most extent of the edge should be further to the + # right + assert padded_extent[0] > default_extent[0] + # And the rightmost extent of the edge, further to the left + assert padded_extent[1] < default_extent[1] + + +# NOTE: parametrizing on marker to test both branches of internal +# nx.draw_networkx_edges.to_marker_edge function +@pytest.mark.parametrize("node_shape", ("o", "s")) +def test_draw_edges_min_source_target_margins_individual(node_shape): + """Test that there is a wider gap between the node and the start of an + incident edge when min_source_margin is specified. + + This test checks that the use of min_{source/target}_margin kwargs result + in shorter (more padding) between the edges and source and target nodes. + As a crude visual example, let 's' and 't' represent source and target + nodes, respectively: + + Default: + s-----------------------------t + + With margins: + s ----------------------- t + + """ + # Create a single axis object to get consistent pixel coords across + # multiple draws + fig, ax = plt.subplots() + G = nx.DiGraph([(0, 1), (1, 2)]) + pos = {0: (0, 0), 1: (1, 0), 2: (2, 0)} # horizontal layout + # Get leftmost and rightmost points of the FancyArrowPatch object + # representing the edge between nodes 0 and 1 (in pixel coordinates) + default_patch = nx.draw_networkx_edges(G, pos, ax=ax, node_shape=node_shape) + default_extent = [d.get_extents().corners()[::2, 0] for d in default_patch] + # Now, do the same but with "padding" for the source and target via the + # min_{source/target}_margin kwargs + padded_patch = nx.draw_networkx_edges( + G, + pos, + ax=ax, + node_shape=node_shape, + min_source_margin=[98, 102], + min_target_margin=[98, 102], + ) + padded_extent = [p.get_extents().corners()[::2, 0] for p in padded_patch] + for d, p in zip(default_extent, padded_extent): + print(f"{p=}, {d=}") + # With padding, the left-most extent of the edge should be further to the + # right + assert p[0] > d[0] + # And the rightmost extent of the edge, further to the left + assert p[1] < d[1] + + +def test_nonzero_selfloop_with_single_node(): + """Ensure that selfloop extent is non-zero when there is only one node.""" + # Create explicit axis object for test + fig, ax = plt.subplots() + # Graph with single node + self loop + G = nx.DiGraph() + G.add_node(0) + G.add_edge(0, 0) + # Draw + patch = nx.draw_networkx_edges(G, {0: (0, 0)})[0] + # The resulting patch must have non-zero extent + bbox = patch.get_extents() + assert bbox.width > 0 and bbox.height > 0 + # Cleanup + plt.delaxes(ax) + plt.close() + + +def test_nonzero_selfloop_with_single_edge_in_edgelist(): + """Ensure that selfloop extent is non-zero when only a single edge is + specified in the edgelist. + """ + # Create explicit axis object for test + fig, ax = plt.subplots() + # Graph with selfloop + G = nx.path_graph(2, create_using=nx.DiGraph) + G.add_edge(1, 1) + pos = {n: (n, n) for n in G.nodes} + # Draw only the selfloop edge via the `edgelist` kwarg + patch = nx.draw_networkx_edges(G, pos, edgelist=[(1, 1)])[0] + # The resulting patch must have non-zero extent + bbox = patch.get_extents() + assert bbox.width > 0 and bbox.height > 0 + # Cleanup + plt.delaxes(ax) + plt.close() + + +def test_apply_alpha(): + """Test apply_alpha when there is a mismatch between the number of + supplied colors and elements. + """ + nodelist = [0, 1, 2] + colorlist = ["r", "g", "b"] + alpha = 0.5 + rgba_colors = nx.drawing.nx_pylab.apply_alpha(colorlist, alpha, nodelist) + assert all(rgba_colors[:, -1] == alpha) + + +def test_draw_edges_toggling_with_arrows_kwarg(): + """ + The `arrows` keyword argument is used as a 3-way switch to select which + type of object to use for drawing edges: + - ``arrows=None`` -> default (FancyArrowPatches for directed, else LineCollection) + - ``arrows=True`` -> FancyArrowPatches + - ``arrows=False`` -> LineCollection + """ + import matplotlib.collections + import matplotlib.patches + + UG = nx.path_graph(3) + DG = nx.path_graph(3, create_using=nx.DiGraph) + pos = {n: (n, n) for n in UG} + + # Use FancyArrowPatches when arrows=True, regardless of graph type + for G in (UG, DG): + edges = nx.draw_networkx_edges(G, pos, arrows=True) + assert len(edges) == len(G.edges) + assert isinstance(edges[0], mpl.patches.FancyArrowPatch) + + # Use LineCollection when arrows=False, regardless of graph type + for G in (UG, DG): + edges = nx.draw_networkx_edges(G, pos, arrows=False) + assert isinstance(edges, mpl.collections.LineCollection) + + # Default behavior when arrows=None: FAPs for directed, LC's for undirected + edges = nx.draw_networkx_edges(UG, pos) + assert isinstance(edges, mpl.collections.LineCollection) + edges = nx.draw_networkx_edges(DG, pos) + assert len(edges) == len(G.edges) + assert isinstance(edges[0], mpl.patches.FancyArrowPatch) + + +@pytest.mark.parametrize("drawing_func", (nx.draw, nx.draw_networkx)) +def test_draw_networkx_arrows_default_undirected(drawing_func): + import matplotlib.collections + + G = nx.path_graph(3) + fig, ax = plt.subplots() + drawing_func(G, ax=ax) + assert any(isinstance(c, mpl.collections.LineCollection) for c in ax.collections) + assert not ax.patches + plt.delaxes(ax) + plt.close() + + +@pytest.mark.parametrize("drawing_func", (nx.draw, nx.draw_networkx)) +def test_draw_networkx_arrows_default_directed(drawing_func): + import matplotlib.collections + + G = nx.path_graph(3, create_using=nx.DiGraph) + fig, ax = plt.subplots() + drawing_func(G, ax=ax) + assert not any( + isinstance(c, mpl.collections.LineCollection) for c in ax.collections + ) + assert ax.patches + plt.delaxes(ax) + plt.close() + + +def test_edgelist_kwarg_not_ignored(): + # See gh-4994 + G = nx.path_graph(3) + G.add_edge(0, 0) + fig, ax = plt.subplots() + nx.draw(G, edgelist=[(0, 1), (1, 2)], ax=ax) # Exclude self-loop from edgelist + assert not ax.patches + plt.delaxes(ax) + plt.close() + + +@pytest.mark.parametrize( + ("G", "expected_n_edges"), + ([nx.DiGraph(), 2], [nx.MultiGraph(), 4], [nx.MultiDiGraph(), 4]), +) +def test_draw_networkx_edges_multiedge_connectionstyle(G, expected_n_edges): + """Draws edges correctly for 3 types of graphs and checks for valid length""" + for i, (u, v) in enumerate([(0, 1), (0, 1), (0, 1), (0, 2)]): + G.add_edge(u, v, weight=round(i / 3, 2)) + pos = {n: (n, n) for n in G} + # Raises on insufficient connectionstyle length + for conn_style in [ + "arc3,rad=0.1", + ["arc3,rad=0.1", "arc3,rad=0.1"], + ["arc3,rad=0.1", "arc3,rad=0.1", "arc3,rad=0.2"], + ]: + nx.draw_networkx_edges(G, pos, connectionstyle=conn_style) + arrows = nx.draw_networkx_edges(G, pos, connectionstyle=conn_style) + assert len(arrows) == expected_n_edges + + +@pytest.mark.parametrize( + ("G", "expected_n_edges"), + ([nx.DiGraph(), 2], [nx.MultiGraph(), 4], [nx.MultiDiGraph(), 4]), +) +def test_draw_networkx_edge_labels_multiedge_connectionstyle(G, expected_n_edges): + """Draws labels correctly for 3 types of graphs and checks for valid length and class names""" + for i, (u, v) in enumerate([(0, 1), (0, 1), (0, 1), (0, 2)]): + G.add_edge(u, v, weight=round(i / 3, 2)) + pos = {n: (n, n) for n in G} + # Raises on insufficient connectionstyle length + arrows = nx.draw_networkx_edges( + G, pos, connectionstyle=["arc3,rad=0.1", "arc3,rad=0.1", "arc3,rad=0.1"] + ) + for conn_style in [ + "arc3,rad=0.1", + ["arc3,rad=0.1", "arc3,rad=0.2"], + ["arc3,rad=0.1", "arc3,rad=0.1", "arc3,rad=0.1"], + ]: + text_items = nx.draw_networkx_edge_labels(G, pos, connectionstyle=conn_style) + assert len(text_items) == expected_n_edges + for ti in text_items.values(): + assert ti.__class__.__name__ == "CurvedArrowText" + + +def test_draw_networkx_edge_label_multiedge(): + G = nx.MultiGraph() + G.add_edge(0, 1, weight=10) + G.add_edge(0, 1, weight=20) + edge_labels = nx.get_edge_attributes(G, "weight") # Includes edge keys + pos = {n: (n, n) for n in G} + text_items = nx.draw_networkx_edge_labels( + G, + pos, + edge_labels=edge_labels, + connectionstyle=["arc3,rad=0.1", "arc3,rad=0.2"], + ) + assert len(text_items) == 2 + + +def test_draw_networkx_edge_label_empty_dict(): + """Regression test for draw_networkx_edge_labels with empty dict. See + gh-5372.""" + G = nx.path_graph(3) + pos = {n: (n, n) for n in G.nodes} + assert nx.draw_networkx_edge_labels(G, pos, edge_labels={}) == {} + + +def test_draw_networkx_edges_undirected_selfloop_colors(): + """When an edgelist is supplied along with a sequence of colors, check that + the self-loops have the correct colors.""" + fig, ax = plt.subplots() + # Edge list and corresponding colors + edgelist = [(1, 3), (1, 2), (2, 3), (1, 1), (3, 3), (2, 2)] + edge_colors = ["pink", "cyan", "black", "red", "blue", "green"] + + G = nx.Graph(edgelist) + pos = {n: (n, n) for n in G.nodes} + nx.draw_networkx_edges(G, pos, ax=ax, edgelist=edgelist, edge_color=edge_colors) + + # Verify that there are three fancy arrow patches (1 per self loop) + assert len(ax.patches) == 3 + + # These are points that should be contained in the self loops. For example, + # sl_points[0] will be (1, 1.1), which is inside the "path" of the first + # self-loop but outside the others + sl_points = np.array(edgelist[-3:]) + np.array([0, 0.1]) + + # Check that the mapping between self-loop locations and their colors is + # correct + for fap, clr, slp in zip(ax.patches, edge_colors[-3:], sl_points): + assert fap.get_path().contains_point(slp) + assert mpl.colors.same_color(fap.get_edgecolor(), clr) + plt.delaxes(ax) + plt.close() + + +@pytest.mark.parametrize( + "fap_only_kwarg", # Non-default values for kwargs that only apply to FAPs + ( + {"arrowstyle": "-"}, + {"arrowsize": 20}, + {"connectionstyle": "arc3,rad=0.2"}, + {"min_source_margin": 10}, + {"min_target_margin": 10}, + ), +) +def test_user_warnings_for_unused_edge_drawing_kwargs(fap_only_kwarg): + """Users should get a warning when they specify a non-default value for + one of the kwargs that applies only to edges drawn with FancyArrowPatches, + but FancyArrowPatches aren't being used under the hood.""" + G = nx.path_graph(3) + pos = {n: (n, n) for n in G} + fig, ax = plt.subplots() + # By default, an undirected graph will use LineCollection to represent + # the edges + kwarg_name = list(fap_only_kwarg.keys())[0] + with pytest.warns( + UserWarning, match=f"\n\nThe {kwarg_name} keyword argument is not applicable" + ): + nx.draw_networkx_edges(G, pos, ax=ax, **fap_only_kwarg) + # FancyArrowPatches are always used when `arrows=True` is specified. + # Check that warnings are *not* raised in this case + with warnings.catch_warnings(): + # Escalate warnings -> errors so tests fail if warnings are raised + warnings.simplefilter("error") + nx.draw_networkx_edges(G, pos, ax=ax, arrows=True, **fap_only_kwarg) + + plt.delaxes(ax) + plt.close() + + +@pytest.mark.parametrize("draw_fn", (nx.draw, nx.draw_circular)) +def test_no_warning_on_default_draw_arrowstyle(draw_fn): + # See gh-7284 + fig, ax = plt.subplots() + G = nx.cycle_graph(5) + with warnings.catch_warnings(record=True) as w: + draw_fn(G, ax=ax) + assert len(w) == 0 + + plt.delaxes(ax) + plt.close() + + +@pytest.mark.parametrize("hide_ticks", [False, True]) +@pytest.mark.parametrize( + "method", + [ + nx.draw_networkx, + nx.draw_networkx_edge_labels, + nx.draw_networkx_edges, + nx.draw_networkx_labels, + nx.draw_networkx_nodes, + ], +) +def test_hide_ticks(method, hide_ticks): + G = nx.path_graph(3) + pos = {n: (n, n) for n in G.nodes} + _, ax = plt.subplots() + method(G, pos=pos, ax=ax, hide_ticks=hide_ticks) + for axis in [ax.xaxis, ax.yaxis]: + assert bool(axis.get_ticklabels()) != hide_ticks + + plt.delaxes(ax) + plt.close() |