small script to plot the weights from a pysal object using polygons in a geopandas dataframe

plotweights.py

import matplotlib.pyplot as plt
import numpy as np

def plot_weights(gdf, W, indexed_on='', ax=None):
    if ax is None:
        f = plt.figure(figsize=(1.6*8, 8))
        ax = plt.gca()
    gdf.plot(linewidth=.1, color='white', ax=ax)
    for idx, neighbors in W:
        if idx in W.islands:
            continue
        if indexed_on != '':
            neighbors = gdf[gdf[indexed_on].isin(neighbors)].index.tolist()
            idx = gdf[gdf[indexed_on] == idx].index.tolist()[0]
        centroids = gdf.ix[neighbors].geometry.apply(lambda pgon: (pgon.centroid.x, pgon.centroid.y))
        centroids = np.vstack(centroids.values)
        focal = np.hstack(gdf.ix[idx].geometry.centroid.xy)
        for neighbor in centroids:
            ax.plot(*zip(focal, neighbor), color='firebrick', linewidth=.1)
    ax.set_xticks([])
    ax.set_yticks([])
    ax.set_title('Rook Contiguity for US Counties')
    return f,ax