FIX spectral_embedding test erros, ADD spectral embedding to sphere examples

Author: weilinear

examples/manifold/plot_manifold_sphere.py

@@ -124,4 +124,19 @@
 ax.yaxis.set_major_formatter(NullFormatter())
 pl.axis('tight')
 
+# Perform Spectral Embedding.
+t0 = time()
+se = manifold.SpectralEmbedding(n_components=2,
+                                n_neighbors=n_neighbors)
+trans_data = se.fit_transform(sphere_data).T
+t1 = time()
+print "Spectral Embedding: %.2g sec" % (t1 - t0)
+
+ax = fig.add_subplot(248)
+pl.scatter(trans_data[0], trans_data[1],  c=colors, cmap=pl.cm.rainbow)
+pl.title("Spectral Embedding (%.2g sec)" % (t1 - t0))
+ax.xaxis.set_major_formatter(NullFormatter())
+ax.yaxis.set_major_formatter(NullFormatter())
+pl.axis('tight')
+
 pl.show()

sklearn/cluster/tests/test_spectral.py

@@ -20,13 +20,13 @@
 
 
 def test_spectral_clustering():
-    S = np.array([[1, 5, 2, 1, 0, 0, 0],
-                  [5, 1, 3, 1, 0, 0, 0],
-                  [2, 3, 1, 1, 0, 0, 0],
-                  [1, 1, 1, 1, 2, 1, 1],
-                  [0, 0, 0, 2, 2, 3, 2],
-                  [0, 0, 0, 1, 3, 1, 4],
-                  [0, 0, 0, 1, 2, 4, 1],
+    S = np.array([[1, 1, 1, 0.2, 0, 0, 0],
+                  [1, 1, 1, 0.2, 0, 0, 0],
+                  [1, 1, 1, 0.2, 0, 0, 0],
+                  [0.2, 0.2, 0.2, 1, 1, 1, 1],
+                  [0, 0, 0, 1, 1, 1, 1],
+                  [0, 0, 0, 1, 1, 1, 1],
+                  [0, 0, 0, 1, 1, 1, 1],
                   ])
 
     for eigen_solver in ('arpack', 'lobpcg'):