Revert "EXA Use stem plot for ElasticNet and Lasso coefficients (scikit-learn#13435)"

Xing · web-flow · commit f9d117d736f1 · 2019-04-28T15:16:17.000-04:00
This reverts commit fa10650.
diff --git a/examples/linear_model/plot_lasso_and_elasticnet.py b/examples/linear_model/plot_lasso_and_elasticnet.py
@@ -19,16 +19,15 @@
 # Generate some sparse data to play with
 np.random.seed(42)
 
-n_samples, n_features = 50, 100
+n_samples, n_features = 50, 200
 X = np.random.randn(n_samples, n_features)
-
-# Decreasing coef w. alternated signs for visualization
-idx = np.arange(n_features)
-coef = (-1) ** idx * np.exp(-idx / 10)
-coef[10:] = 0  # sparsify coef
+coef = 3 * np.random.randn(n_features)
+inds = np.arange(n_features)
+np.random.shuffle(inds)
+coef[inds[10:]] = 0  # sparsify coef
 y = np.dot(X, coef)
 
-# Add noise
+# add noise
 y += 0.01 * np.random.normal(size=n_samples)
 
 # Split data in train set and test set
@@ -59,16 +58,12 @@
 print(enet)
 print("r^2 on test data : %f" % r2_score_enet)
 
-m, s, _ = plt.stem(np.where(enet.coef_)[0], enet.coef_[enet.coef_ != 0],
-                   markerfmt='x', label='Elastic net coefficients')
-plt.setp([m, s], color="#2ca02c")
-m, s, _ = plt.stem(np.where(lasso.coef_)[0], lasso.coef_[lasso.coef_ != 0],
-                   markerfmt='x', label='Lasso coefficients')
-plt.setp([m, s], color='#ff7f0e')
-plt.stem(np.where(coef)[0], coef[coef != 0], label='true coefficients',
-         markerfmt='bx')
-
+plt.plot(enet.coef_, color='lightgreen', linewidth=2,
+         label='Elastic net coefficients')
+plt.plot(lasso.coef_, color='gold', linewidth=2,
+         label='Lasso coefficients')
+plt.plot(coef, '--', color='navy', label='original coefficients')
 plt.legend(loc='best')
-plt.title("Lasso $R^2$: %.3f, Elastic Net $R^2$: %.3f"
+plt.title("Lasso R^2: %f, Elastic Net R^2: %f"
           % (r2_score_lasso, r2_score_enet))
 plt.show()
