Dimensionality Reduction with MDS


In [1]:
%matplotlib inline
import matplotlib.pyplot as plt
import seaborn as sns
import pandas as pd

from sklearn import manifold, datasets
from matplotlib.colors import ListedColormap

In [2]:
iris = datasets.load_iris()
mds = manifold.MDS(n_components=2)
new_dim = mds.fit_transform(iris.data)

In [3]:
df = pd.DataFrame(new_dim, columns=['X', 'Y'])
df['label'] = iris.target
df.head()


Out[3]:
X Y label
0 2.150776 -1.657853 0
1 1.802691 -2.051461 0
2 1.998624 -2.112414 0
3 1.749715 -2.150154 0
4 2.209121 -1.666944 0

In [4]:
fig = plt.figure()
fig.suptitle('MDS', fontsize=14, fontweight='bold')
ax = fig.add_subplot(111)

plt.scatter(df[df.label == 0].X, df[df.label == 0].Y, color='red', label=iris.target_names[0])
plt.scatter(df[df.label == 1].X, df[df.label == 1].Y, color='blue', label=iris.target_names[1])
plt.scatter(df[df.label == 2].X, df[df.label == 2].Y, color='green', label=iris.target_names[2])

plt.legend(bbox_to_anchor=(1.25, 1))


Out[4]:
<matplotlib.legend.Legend at 0x10c2b6390>