Warning

This documents an unmaintained version of NetworkX. Please upgrade to a maintained version and see the current NetworkX documentation.

Source code for networkx.drawing.nx_pylab

#    Copyright (C) 2004-2018 by
#    Aric Hagberg <hagberg@lanl.gov>
#    Dan Schult <dschult@colgate.edu>
#    Pieter Swart <swart@lanl.gov>
#    All rights reserved.
#    BSD license.
#
# Author: Aric Hagberg (hagberg@lanl.gov)
"""
**********
Matplotlib
**********

Draw networks with matplotlib.

See Also
--------

matplotlib:     http://matplotlib.org/

pygraphviz:     http://pygraphviz.github.io/

"""
import networkx as nx
from networkx.utils import is_string_like
from networkx.drawing.layout import shell_layout, \
    circular_layout, kamada_kawai_layout, spectral_layout, \
    spring_layout, random_layout

__all__ = ['draw',
           'draw_networkx',
           'draw_networkx_nodes',
           'draw_networkx_edges',
           'draw_networkx_labels',
           'draw_networkx_edge_labels',
           'draw_circular',
           'draw_kamada_kawai',
           'draw_random',
           'draw_spectral',
           'draw_spring',
           'draw_shell']


[docs]def draw(G, pos=None, ax=None, **kwds): """Draw the graph G with Matplotlib. Draw the graph as a simple representation with no node labels or edge labels and using the full Matplotlib figure area and no axis labels by default. See draw_networkx() for more full-featured drawing that allows title, axis labels etc. Parameters ---------- G : graph A networkx graph pos : dictionary, optional A dictionary with nodes as keys and positions as values. If not specified a spring layout positioning will be computed. See :py:mod:`networkx.drawing.layout` for functions that compute node positions. ax : Matplotlib Axes object, optional Draw the graph in specified Matplotlib axes. kwds : optional keywords See networkx.draw_networkx() for a description of optional keywords. Examples -------- >>> G = nx.dodecahedral_graph() >>> nx.draw(G) >>> nx.draw(G, pos=nx.spring_layout(G)) # use spring layout See Also -------- draw_networkx() draw_networkx_nodes() draw_networkx_edges() draw_networkx_labels() draw_networkx_edge_labels() Notes ----- This function has the same name as pylab.draw and pyplot.draw so beware when using >>> from networkx import * since you might overwrite the pylab.draw function. With pyplot use >>> import matplotlib.pyplot as plt >>> import networkx as nx >>> G = nx.dodecahedral_graph() >>> nx.draw(G) # networkx draw() >>> plt.draw() # pyplot draw() Also see the NetworkX drawing examples at https://networkx.org/documentation/latest/auto_examples/index.html """ try: import matplotlib.pyplot as plt except ImportError: raise ImportError("Matplotlib required for draw()") except RuntimeError: print("Matplotlib unable to open display") raise if ax is None: cf = plt.gcf() else: cf = ax.get_figure() cf.set_facecolor('w') if ax is None: if cf._axstack() is None: ax = cf.add_axes((0, 0, 1, 1)) else: ax = cf.gca() if 'with_labels' not in kwds: kwds['with_labels'] = 'labels' in kwds try: draw_networkx(G, pos=pos, ax=ax, **kwds) ax.set_axis_off() plt.draw_if_interactive() except: raise return
[docs]def draw_networkx(G, pos=None, arrows=True, with_labels=True, **kwds): """Draw the graph G using Matplotlib. Draw the graph with Matplotlib with options for node positions, labeling, titles, and many other drawing features. See draw() for simple drawing without labels or axes. Parameters ---------- G : graph A networkx graph pos : dictionary, optional A dictionary with nodes as keys and positions as values. If not specified a spring layout positioning will be computed. See :py:mod:`networkx.drawing.layout` for functions that compute node positions. arrows : bool, optional (default=True) For directed graphs, if True draw arrowheads. Note: Arrows will be the same color as edges. arrowstyle : str, optional (default='-|>') For directed graphs, choose the style of the arrowsheads. See :py:class: `matplotlib.patches.ArrowStyle` for more options. arrowsize : int, optional (default=10) For directed graphs, choose the size of the arrow head head's length and width. See :py:class: `matplotlib.patches.FancyArrowPatch` for attribute `mutation_scale` for more info. with_labels : bool, optional (default=True) Set to True to draw labels on the nodes. ax : Matplotlib Axes object, optional Draw the graph in the specified Matplotlib axes. nodelist : list, optional (default G.nodes()) Draw only specified nodes edgelist : list, optional (default=G.edges()) Draw only specified edges node_size : scalar or array, optional (default=300) Size of nodes. If an array is specified it must be the same length as nodelist. node_color : color string, or array of floats, (default='r') Node color. Can be a single color format string, or a sequence of colors with the same length as nodelist. If numeric values are specified they will be mapped to colors using the cmap and vmin,vmax parameters. See matplotlib.scatter for more details. node_shape : string, optional (default='o') The shape of the node. Specification is as matplotlib.scatter marker, one of 'so^>v<dph8'. alpha : float, optional (default=1.0) The node and edge transparency cmap : Matplotlib colormap, optional (default=None) Colormap for mapping intensities of nodes vmin,vmax : float, optional (default=None) Minimum and maximum for node colormap scaling linewidths : [None | scalar | sequence] Line width of symbol border (default =1.0) width : float, optional (default=1.0) Line width of edges edge_color : color string, or array of floats (default='r') Edge color. Can be a single color format string, or a sequence of colors with the same length as edgelist. If numeric values are specified they will be mapped to colors using the edge_cmap and edge_vmin,edge_vmax parameters. edge_cmap : Matplotlib colormap, optional (default=None) Colormap for mapping intensities of edges edge_vmin,edge_vmax : floats, optional (default=None) Minimum and maximum for edge colormap scaling style : string, optional (default='solid') Edge line style (solid|dashed|dotted,dashdot) labels : dictionary, optional (default=None) Node labels in a dictionary keyed by node of text labels font_size : int, optional (default=12) Font size for text labels font_color : string, optional (default='k' black) Font color string font_weight : string, optional (default='normal') Font weight font_family : string, optional (default='sans-serif') Font family label : string, optional Label for graph legend Notes ----- For directed graphs, arrows are drawn at the head end. Arrows can be turned off with keyword arrows=False. Examples -------- >>> G = nx.dodecahedral_graph() >>> nx.draw(G) >>> nx.draw(G, pos=nx.spring_layout(G)) # use spring layout >>> import matplotlib.pyplot as plt >>> limits = plt.axis('off') # turn of axis Also see the NetworkX drawing examples at https://networkx.org/documentation/latest/auto_examples/index.html See Also -------- draw() draw_networkx_nodes() draw_networkx_edges() draw_networkx_labels() draw_networkx_edge_labels() """ try: import matplotlib.pyplot as plt except ImportError: raise ImportError("Matplotlib required for draw()") except RuntimeError: print("Matplotlib unable to open display") raise if pos is None: pos = nx.drawing.spring_layout(G) # default to spring layout node_collection = draw_networkx_nodes(G, pos, **kwds) edge_collection = draw_networkx_edges(G, pos, arrows=arrows, **kwds) if with_labels: draw_networkx_labels(G, pos, **kwds) plt.draw_if_interactive()
[docs]def draw_networkx_nodes(G, pos, nodelist=None, node_size=300, node_color='r', node_shape='o', alpha=1.0, cmap=None, vmin=None, vmax=None, ax=None, linewidths=None, edgecolors=None, label=None, **kwds): """Draw the nodes of the graph G. This draws only the nodes of the graph G. Parameters ---------- G : graph A networkx graph pos : dictionary A dictionary with nodes as keys and positions as values. Positions should be sequences of length 2. ax : Matplotlib Axes object, optional Draw the graph in the specified Matplotlib axes. nodelist : list, optional Draw only specified nodes (default G.nodes()) node_size : scalar or array Size of nodes (default=300). If an array is specified it must be the same length as nodelist. node_color : color string, or array of floats Node color. Can be a single color format string (default='r'), or a sequence of colors with the same length as nodelist. If numeric values are specified they will be mapped to colors using the cmap and vmin,vmax parameters. See matplotlib.scatter for more details. node_shape : string The shape of the node. Specification is as matplotlib.scatter marker, one of 'so^>v<dph8' (default='o'). alpha : float or array of floats The node transparency. This can be a single alpha value (default=1.0), in which case it will be applied to all the nodes of color. Otherwise, if it is an array, the elements of alpha will be applied to the colors in order (cycling through alpha multiple times if necessary). cmap : Matplotlib colormap Colormap for mapping intensities of nodes (default=None) vmin,vmax : floats Minimum and maximum for node colormap scaling (default=None) linewidths : [None | scalar | sequence] Line width of symbol border (default =1.0) edgecolors : [None | scalar | sequence] Colors of node borders (default = node_color) label : [None| string] Label for legend Returns ------- matplotlib.collections.PathCollection `PathCollection` of the nodes. Examples -------- >>> G = nx.dodecahedral_graph() >>> nodes = nx.draw_networkx_nodes(G, pos=nx.spring_layout(G)) Also see the NetworkX drawing examples at https://networkx.org/documentation/latest/auto_examples/index.html See Also -------- draw() draw_networkx() draw_networkx_edges() draw_networkx_labels() draw_networkx_edge_labels() """ import collections try: import matplotlib.pyplot as plt import numpy as np except ImportError: raise ImportError("Matplotlib required for draw()") except RuntimeError: print("Matplotlib unable to open display") raise if ax is None: ax = plt.gca() if nodelist is None: nodelist = list(G) if not nodelist or len(nodelist) == 0: # empty nodelist, no drawing return None try: xy = np.asarray([pos[v] for v in nodelist]) except KeyError as e: raise nx.NetworkXError('Node %s has no position.' % e) except ValueError: raise nx.NetworkXError('Bad value in node positions.') if isinstance(alpha, collections.Iterable): node_color = apply_alpha(node_color, alpha, nodelist, cmap, vmin, vmax) alpha = None node_collection = ax.scatter(xy[:, 0], xy[:, 1], s=node_size, c=node_color, marker=node_shape, cmap=cmap, vmin=vmin, vmax=vmax, alpha=alpha, linewidths=linewidths, edgecolors=edgecolors, label=label) node_collection.set_zorder(2) return node_collection
[docs]def draw_networkx_edges(G, pos, edgelist=None, width=1.0, edge_color='k', style='solid', alpha=1.0, arrowstyle='-|>', arrowsize=10, edge_cmap=None, edge_vmin=None, edge_vmax=None, ax=None, arrows=True, label=None, node_size=300, nodelist=None, node_shape="o", **kwds): """Draw the edges of the graph G. This draws only the edges of the graph G. Parameters ---------- G : graph A networkx graph pos : dictionary A dictionary with nodes as keys and positions as values. Positions should be sequences of length 2. edgelist : collection of edge tuples Draw only specified edges(default=G.edges()) width : float, or array of floats Line width of edges (default=1.0) edge_color : color string, or array of floats Edge color. Can be a single color format string (default='r'), or a sequence of colors with the same length as edgelist. If numeric values are specified they will be mapped to colors using the edge_cmap and edge_vmin,edge_vmax parameters. style : string Edge line style (default='solid') (solid|dashed|dotted,dashdot) alpha : float The edge transparency (default=1.0) edge_ cmap : Matplotlib colormap Colormap for mapping intensities of edges (default=None) edge_vmin,edge_vmax : floats Minimum and maximum for edge colormap scaling (default=None) ax : Matplotlib Axes object, optional Draw the graph in the specified Matplotlib axes. arrows : bool, optional (default=True) For directed graphs, if True draw arrowheads. Note: Arrows will be the same color as edges. arrowstyle : str, optional (default='-|>') For directed graphs, choose the style of the arrow heads. See :py:class: `matplotlib.patches.ArrowStyle` for more options. arrowsize : int, optional (default=10) For directed graphs, choose the size of the arrow head head's length and width. See :py:class: `matplotlib.patches.FancyArrowPatch` for attribute `mutation_scale` for more info. label : [None| string] Label for legend Returns ------- matplotlib.collection.LineCollection `LineCollection` of the edges list of matplotlib.patches.FancyArrowPatch `FancyArrowPatch` instances of the directed edges Depending whether the drawing includes arrows or not. Notes ----- For directed graphs, arrows are drawn at the head end. Arrows can be turned off with keyword arrows=False. Be sure to include `node_size' as a keyword argument; arrows are drawn considering the size of nodes. Examples -------- >>> G = nx.dodecahedral_graph() >>> edges = nx.draw_networkx_edges(G, pos=nx.spring_layout(G)) >>> G = nx.DiGraph() >>> G.add_edges_from([(1, 2), (1, 3), (2, 3)]) >>> arcs = nx.draw_networkx_edges(G, pos=nx.spring_layout(G)) >>> alphas = [0.3, 0.4, 0.5] >>> for i, arc in enumerate(arcs): # change alpha values of arcs ... arc.set_alpha(alphas[i]) Also see the NetworkX drawing examples at https://networkx.org/documentation/latest/auto_examples/index.html See Also -------- draw() draw_networkx() draw_networkx_nodes() draw_networkx_labels() draw_networkx_edge_labels() """ try: import matplotlib import matplotlib.pyplot as plt import matplotlib.cbook as cb from matplotlib.colors import colorConverter, Colormap, Normalize from matplotlib.collections import LineCollection from matplotlib.patches import FancyArrowPatch import numpy as np except ImportError: raise ImportError("Matplotlib required for draw()") except RuntimeError: print("Matplotlib unable to open display") raise if ax is None: ax = plt.gca() if edgelist is None: edgelist = list(G.edges()) if not edgelist or len(edgelist) == 0: # no edges! return None if nodelist is None: nodelist = list(G.nodes()) # set edge positions edge_pos = np.asarray([(pos[e[0]], pos[e[1]]) for e in edgelist]) if not cb.iterable(width): lw = (width,) else: lw = width if not is_string_like(edge_color) \ and cb.iterable(edge_color) \ and len(edge_color) == len(edge_pos): if np.alltrue([is_string_like(c) for c in edge_color]): # (should check ALL elements) # list of color letters such as ['k','r','k',...] edge_colors = tuple([colorConverter.to_rgba(c, alpha) for c in edge_color]) elif np.alltrue([not is_string_like(c) for c in edge_color]): # If color specs are given as (rgb) or (rgba) tuples, we're OK if np.alltrue([cb.iterable(c) and len(c) in (3, 4) for c in edge_color]): edge_colors = tuple(edge_color) else: # numbers (which are going to be mapped with a colormap) edge_colors = None else: raise ValueError('edge_color must contain color names or numbers') else: if is_string_like(edge_color) or len(edge_color) == 1: edge_colors = (colorConverter.to_rgba(edge_color, alpha), ) else: msg = 'edge_color must be a color or list of one color per edge' raise ValueError(msg) if (not G.is_directed() or not arrows): edge_collection = LineCollection(edge_pos, colors=edge_colors, linewidths=lw, antialiaseds=(1,), linestyle=style, transOffset=ax.transData, ) edge_collection.set_zorder(1) # edges go behind nodes edge_collection.set_label(label) ax.add_collection(edge_collection) # Note: there was a bug in mpl regarding the handling of alpha values # for each line in a LineCollection. It was fixed in matplotlib by # r7184 and r7189 (June 6 2009). We should then not set the alpha # value globally, since the user can instead provide per-edge alphas # now. Only set it globally if provided as a scalar. if cb.is_numlike(alpha): edge_collection.set_alpha(alpha) if edge_colors is None: if edge_cmap is not None: assert(isinstance(edge_cmap, Colormap)) edge_collection.set_array(np.asarray(edge_color)) edge_collection.set_cmap(edge_cmap) if edge_vmin is not None or edge_vmax is not None: edge_collection.set_clim(edge_vmin, edge_vmax) else: edge_collection.autoscale() return edge_collection arrow_collection = None if G.is_directed() and arrows: # Note: Waiting for someone to implement arrow to intersection with # marker. Meanwhile, this works well for polygons with more than 4 # sides and circle. def to_marker_edge(marker_size, marker): if marker in "s^>v<d": # `large` markers need extra space return np.sqrt(2 * marker_size) / 2 else: return np.sqrt(marker_size) / 2 # Draw arrows with `matplotlib.patches.FancyarrowPatch` arrow_collection = [] mutation_scale = arrowsize # scale factor of arrow head arrow_colors = edge_colors if arrow_colors is None: if edge_cmap is not None: assert(isinstance(edge_cmap, Colormap)) else: edge_cmap = plt.get_cmap() # default matplotlib colormap if edge_vmin is None: edge_vmin = min(edge_color) if edge_vmax is None: edge_vmax = max(edge_color) color_normal = Normalize(vmin=edge_vmin, vmax=edge_vmax) for i, (src, dst) in enumerate(edge_pos): x1, y1 = src x2, y2 = dst arrow_color = None line_width = None shrink_source = 0 # space from source to tail shrink_target = 0 # space from head to target if cb.iterable(node_size): # many node sizes src_node, dst_node = edgelist[i] index_node = nodelist.index(dst_node) marker_size = node_size[index_node] shrink_target = to_marker_edge(marker_size, node_shape) else: shrink_target = to_marker_edge(node_size, node_shape) if arrow_colors is None: arrow_color = edge_cmap(color_normal(edge_color[i])) elif len(arrow_colors) > 1: arrow_color = arrow_colors[i] else: arrow_color = arrow_colors[0] if len(lw) > 1: line_width = lw[i] else: line_width = lw[0] arrow = FancyArrowPatch((x1, y1), (x2, y2), arrowstyle=arrowstyle, shrinkA=shrink_source, shrinkB=shrink_target, mutation_scale=mutation_scale, color=arrow_color, linewidth=line_width, zorder=1) # arrows go behind nodes # There seems to be a bug in matplotlib to make collections of # FancyArrowPatch instances. Until fixed, the patches are added # individually to the axes instance. arrow_collection.append(arrow) ax.add_patch(arrow) # update view minx = np.amin(np.ravel(edge_pos[:, :, 0])) maxx = np.amax(np.ravel(edge_pos[:, :, 0])) miny = np.amin(np.ravel(edge_pos[:, :, 1])) maxy = np.amax(np.ravel(edge_pos[:, :, 1])) w = maxx - minx h = maxy - miny padx, pady = 0.05 * w, 0.05 * h corners = (minx - padx, miny - pady), (maxx + padx, maxy + pady) ax.update_datalim(corners) ax.autoscale_view() return arrow_collection
[docs]def draw_networkx_labels(G, pos, labels=None, font_size=12, font_color='k', font_family='sans-serif', font_weight='normal', alpha=1.0, bbox=None, ax=None, **kwds): """Draw node labels on the graph G. Parameters ---------- G : graph A networkx graph pos : dictionary A dictionary with nodes as keys and positions as values. Positions should be sequences of length 2. labels : dictionary, optional (default=None) Node labels in a dictionary keyed by node of text labels font_size : int Font size for text labels (default=12) font_color : string Font color string (default='k' black) font_family : string Font family (default='sans-serif') font_weight : string Font weight (default='normal') alpha : float The text transparency (default=1.0) ax : Matplotlib Axes object, optional Draw the graph in the specified Matplotlib axes. Returns ------- dict `dict` of labels keyed on the nodes Examples -------- >>> G = nx.dodecahedral_graph() >>> labels = nx.draw_networkx_labels(G, pos=nx.spring_layout(G)) Also see the NetworkX drawing examples at https://networkx.org/documentation/latest/auto_examples/index.html See Also -------- draw() draw_networkx() draw_networkx_nodes() draw_networkx_edges() draw_networkx_edge_labels() """ try: import matplotlib.pyplot as plt import matplotlib.cbook as cb except ImportError: raise ImportError("Matplotlib required for draw()") except RuntimeError: print("Matplotlib unable to open display") raise if ax is None: ax = plt.gca() if labels is None: labels = dict((n, n) for n in G.nodes()) # set optional alignment horizontalalignment = kwds.get('horizontalalignment', 'center') verticalalignment = kwds.get('verticalalignment', 'center') text_items = {} # there is no text collection so we'll fake one for n, label in labels.items(): (x, y) = pos[n] if not is_string_like(label): label = str(label) # this makes "1" and 1 labeled the same t = ax.text(x, y, label, size=font_size, color=font_color, family=font_family, weight=font_weight, alpha=alpha, horizontalalignment=horizontalalignment, verticalalignment=verticalalignment, transform=ax.transData, bbox=bbox, clip_on=True, ) text_items[n] = t return text_items
[docs]def draw_networkx_edge_labels(G, pos, edge_labels=None, label_pos=0.5, font_size=10, font_color='k', font_family='sans-serif', font_weight='normal', alpha=1.0, bbox=None, ax=None, rotate=True, **kwds): """Draw edge labels. Parameters ---------- G : graph A networkx graph pos : dictionary A dictionary with nodes as keys and positions as values. Positions should be sequences of length 2. ax : Matplotlib Axes object, optional Draw the graph in the specified Matplotlib axes. alpha : float The text transparency (default=1.0) edge_labels : dictionary Edge labels in a dictionary keyed by edge two-tuple of text labels (default=None). Only labels for the keys in the dictionary are drawn. label_pos : float Position of edge label along edge (0=head, 0.5=center, 1=tail) font_size : int Font size for text labels (default=12) font_color : string Font color string (default='k' black) font_weight : string Font weight (default='normal') font_family : string Font family (default='sans-serif') bbox : Matplotlib bbox Specify text box shape and colors. clip_on : bool Turn on clipping at axis boundaries (default=True) Returns ------- dict `dict` of labels keyed on the edges Examples -------- >>> G = nx.dodecahedral_graph() >>> edge_labels = nx.draw_networkx_edge_labels(G, pos=nx.spring_layout(G)) Also see the NetworkX drawing examples at https://networkx.org/documentation/latest/auto_examples/index.html See Also -------- draw() draw_networkx() draw_networkx_nodes() draw_networkx_edges() draw_networkx_labels() """ try: import matplotlib.pyplot as plt import numpy as np except ImportError: raise ImportError("Matplotlib required for draw()") except RuntimeError: print("Matplotlib unable to open display") raise if ax is None: ax = plt.gca() if edge_labels is None: labels = {(u, v): d for u, v, d in G.edges(data=True)} else: labels = edge_labels text_items = {} for (n1, n2), label in labels.items(): (x1, y1) = pos[n1] (x2, y2) = pos[n2] (x, y) = (x1 * label_pos + x2 * (1.0 - label_pos), y1 * label_pos + y2 * (1.0 - label_pos)) if rotate: # in degrees angle = np.arctan2(y2 - y1, x2 - x1) / (2.0 * np.pi) * 360 # make label orientation "right-side-up" if angle > 90: angle -= 180 if angle < - 90: angle += 180 # transform data coordinate angle to screen coordinate angle xy = np.array((x, y)) trans_angle = ax.transData.transform_angles(np.array((angle,)), xy.reshape((1, 2)))[0] else: trans_angle = 0.0 # use default box of white with white border if bbox is None: bbox = dict(boxstyle='round', ec=(1.0, 1.0, 1.0), fc=(1.0, 1.0, 1.0), ) if not is_string_like(label): label = str(label) # this makes "1" and 1 labeled the same # set optional alignment horizontalalignment = kwds.get('horizontalalignment', 'center') verticalalignment = kwds.get('verticalalignment', 'center') t = ax.text(x, y, label, size=font_size, color=font_color, family=font_family, weight=font_weight, alpha=alpha, horizontalalignment=horizontalalignment, verticalalignment=verticalalignment, rotation=trans_angle, transform=ax.transData, bbox=bbox, zorder=1, clip_on=True, ) text_items[(n1, n2)] = t return text_items
[docs]def draw_circular(G, **kwargs): """Draw the graph G with a circular layout. Parameters ---------- G : graph A networkx graph kwargs : optional keywords See networkx.draw_networkx() for a description of optional keywords, with the exception of the pos parameter which is not used by this function. """ draw(G, circular_layout(G), **kwargs)
[docs]def draw_kamada_kawai(G, **kwargs): """Draw the graph G with a Kamada-Kawai force-directed layout. Parameters ---------- G : graph A networkx graph kwargs : optional keywords See networkx.draw_networkx() for a description of optional keywords, with the exception of the pos parameter which is not used by this function. """ draw(G, kamada_kawai_layout(G), **kwargs)
[docs]def draw_random(G, **kwargs): """Draw the graph G with a random layout. Parameters ---------- G : graph A networkx graph kwargs : optional keywords See networkx.draw_networkx() for a description of optional keywords, with the exception of the pos parameter which is not used by this function. """ draw(G, random_layout(G), **kwargs)
[docs]def draw_spectral(G, **kwargs): """Draw the graph G with a spectral layout. Parameters ---------- G : graph A networkx graph kwargs : optional keywords See networkx.draw_networkx() for a description of optional keywords, with the exception of the pos parameter which is not used by this function. """ draw(G, spectral_layout(G), **kwargs)
[docs]def draw_spring(G, **kwargs): """Draw the graph G with a spring layout. Parameters ---------- G : graph A networkx graph kwargs : optional keywords See networkx.draw_networkx() for a description of optional keywords, with the exception of the pos parameter which is not used by this function. """ draw(G, spring_layout(G), **kwargs)
[docs]def draw_shell(G, **kwargs): """Draw networkx graph with shell layout. Parameters ---------- G : graph A networkx graph kwargs : optional keywords See networkx.draw_networkx() for a description of optional keywords, with the exception of the pos parameter which is not used by this function. """ nlist = kwargs.get('nlist', None) if nlist is not None: del(kwargs['nlist']) draw(G, shell_layout(G, nlist=nlist), **kwargs)
def apply_alpha(colors, alpha, elem_list, cmap=None, vmin=None, vmax=None): """Apply an alpha (or list of alphas) to the colors provided. Parameters ---------- colors : color string, or array of floats Color of element. Can be a single color format string (default='r'), or a sequence of colors with the same length as nodelist. If numeric values are specified they will be mapped to colors using the cmap and vmin,vmax parameters. See matplotlib.scatter for more details. alpha : float or array of floats Alpha values for elements. This can be a single alpha value, in which case it will be applied to all the elements of color. Otherwise, if it is an array, the elements of alpha will be applied to the colors in order (cycling through alpha multiple times if necessary). elem_list : array of networkx objects The list of elements which are being colored. These could be nodes, edges or labels. cmap : matplotlib colormap Color map for use if colors is a list of floats corresponding to points on a color mapping. vmin, vmax : float Minimum and maximum values for normalizing colors if a color mapping is used. Returns ------- rgba_colors : numpy ndarray Array containing RGBA format values for each of the node colours. """ import numbers from itertools import islice, cycle try: import numpy as np from matplotlib.colors import colorConverter import matplotlib.cm as cm except ImportError: raise ImportError("Matplotlib required for draw()") # If we have been provided with a list of numbers as long as elem_list, # apply the color mapping. if len(colors) == len(elem_list) and isinstance(colors[0], numbers.Number): mapper = cm.ScalarMappable(cmap=cmap) mapper.set_clim(vmin, vmax) rgba_colors = mapper.to_rgba(colors) # Otherwise, convert colors to matplotlib's RGB using the colorConverter # object. These are converted to numpy ndarrays to be consistent with the # to_rgba method of ScalarMappable. else: try: rgba_colors = np.array([colorConverter.to_rgba(colors)]) except ValueError: rgba_colors = np.array([colorConverter.to_rgba(color) for color in colors]) # Set the final column of the rgba_colors to have the relevant alpha values try: # If alpha is longer than the number of colors, resize to the number of # elements. Also, if rgba_colors.size (the number of elements of # rgba_colors) is the same as the number of elements, resize the array, # to avoid it being interpreted as a colormap by scatter() if len(alpha) > len(rgba_colors) or rgba_colors.size == len(elem_list): rgba_colors.resize((len(elem_list), 4)) rgba_colors[1:, 0] = rgba_colors[0, 0] rgba_colors[1:, 1] = rgba_colors[0, 1] rgba_colors[1:, 2] = rgba_colors[0, 2] rgba_colors[:, 3] = list(islice(cycle(alpha), len(rgba_colors))) except TypeError: rgba_colors[:, -1] = alpha return rgba_colors # fixture for nose tests def setup_module(module): from nose import SkipTest try: import matplotlib as mpl mpl.use('PS', warn=False) import matplotlib.pyplot as plt except: raise SkipTest("matplotlib not available")