def G_to_wkt()

in libs/apls/skeletonize.py [0:0]

• 66 lines of code
• 33 McCabe index (conditional complexity)

def G_to_wkt(G, add_small=True,
             debug=False, verbose=False, super_verbose=False):
    """Transform G to wkt"""

    if G == [linestring.format("EMPTY")] or type(G) == str:
        return [linestring.format("EMPTY")]
    node_lines = graph2lines(G)

    if not node_lines:
        return [linestring.format("EMPTY")]
    try: # later version of networkx
        node = G.nodes
    except: # legacy networkx
        node = G.node
    deg = dict(G.degree())
    wkt = []
    terminal_points = [i for i, d in deg.items() if d == 1]

    # refine wkt
    terminal_lines = {}
    vertices = []
    for i, w in enumerate(node_lines):
        if ((i % 10000) == 0) and (i > 0) and verbose:
            print("  ", i, "/", len(node_lines))
        coord_list = []
        additional_paths = []
        for s, e in pairwise(w):
            vals = flatten([[v] for v in G[s][e].values()])
            for ix, val in enumerate(vals):

                s_coord, e_coord = node[s]['o'], node[e]['o']
                pts = val.get('pts', [])
                if s in terminal_points:
                    terminal_lines[s] = (s_coord, e_coord)
                if e in terminal_points:
                    terminal_lines[e] = (e_coord, s_coord)

                ps = add_direction_change_nodes(pts, s, e, s_coord, e_coord)

                if len(ps.shape) < 2 or len(ps) < 2:
                    continue
                if len(ps) == 2 and np.all(ps[0] == ps[1]):
                    continue

                line_strings = ["{1:.1f} {0:.1f}".format(*c.tolist()) for c in ps]
                if ix == 0:
                    coord_list.extend(line_strings)
                else:
                    additional_paths.append(line_strings)

                vertices.append(ps)

        if not len(coord_list):
            continue
        segments = remove_duplicate_segments(coord_list)
    
        for coord_list in segments:
            if len(coord_list) > 1:
                line = '(' + ", ".join(coord_list) + ')'
                wkt.append(linestring.format(line))
        for line_strings in additional_paths:
            line = ", ".join(line_strings)
            line_rev = ", ".join(reversed(line_strings))
            for s in wkt:
                if line in s or line_rev in s:
                    break
            else:
                wkt.append(linestring.format('(' + line + ')'))

    if add_small and len(terminal_points) > 1:
        small_segs, good_pairs, good_coords = add_small_segments(
            G, terminal_points, terminal_lines, verbose=verbose)
        if verbose: print("small_segs", small_segs)
        wkt.extend(small_segs)

    if debug:
        vertices = flatten(vertices)

    if not wkt:
        return [linestring.format("EMPTY")]
    return wkt