Three Blobs Dataset

A function that loads the three_blobs dataset into NumPy arrays.

from mlxtend.data import three_blobs_data

Overview

A random dataset of 3 2D blobs for clustering.

  • Number of samples : 150
  • Suggested labels {0, 1, 2}, distribution: [50, 50, 50]

References

Example 1 - Dataset overview

from mlxtend.data import three_blobs_data
X, y = three_blobs_data()

print('Dimensions: %s x %s' % (X.shape[0], X.shape[1]))

print('1st row', X[0])
Dimensions: 150 x 2
1st row [ 2.60509732  1.22529553]
import numpy as np

print('Suggested cluster labels')
print(np.unique(y))
print('Label distribution: %s' % np.bincount(y))
Suggested cluster labels
[0 1 2]
Label distribution: [50 50 50]
import matplotlib.pyplot as plt

plt.scatter(X[:,0], X[:,1],
            c='white',
            marker='o',
            s=50)

plt.grid()
plt.show()

png

plt.scatter(X[y == 0, 0],
            X[y == 0, 1],
            s=50,
            c='lightgreen',
            marker='s',
            label='cluster 1')

plt.scatter(X[y == 1,0],
            X[y == 1,1],
            s=50,
            c='orange',
            marker='o',
            label='cluster 2')

plt.scatter(X[y == 2,0],
            X[y == 2,1],
            s=50,
            c='lightblue',
            marker='v',
            label='cluster 3')

plt.legend(loc='lower left')
plt.grid()
plt.show()

png

API

three_blobs_data()

A random dataset of 3 2D blobs for clustering.

  • Number of samples : 150

  • Suggested labels : {0, 1, 2}, distribution: [50, 50, 50]

Returns

  • X, y : [n_samples, n_features], [n_cluster_labels]

    X is the feature matrix with 159 samples as rows and 2 feature columns. y is a 1-dimensional array of the 3 suggested cluster labels 0, 1, 2