gistfile1.py

loadings = pca.components_

# I've omitted the code to create ind; a list of the indexes of the
# loadings ordered by distance from origin.

plt.scatter(*loadings, alpha=0.3, label="Loadings");
plt.scatter(*loadings[:, ind[:3]], c='r', marker='o',
            s=80, linewidths=1, facecolors="none", 
            edgecolors='r', 
            label="Contributes most\nto variance");

plt.title("Loading plot");
plt.xlabel("Loadings on PC1");
plt.ylabel("Loadings on PC2");
plt.grid();
plt.legend(loc='lower left');