File: ex1.py

package info (click to toggle)
python-scipy 0.14.0-2
  • links: PTS, VCS
  • area: main
  • in suites: jessie, jessie-kfreebsd
  • size: 52,228 kB
  • ctags: 63,719
  • sloc: python: 112,726; fortran: 88,685; cpp: 86,979; ansic: 85,860; makefile: 530; sh: 236
file content (40 lines) | stat: -rwxr-xr-x 1,282 bytes parent folder | download
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
from __future__ import division, print_function, absolute_import

from scipy import *
from scipy.cluster import vq


def cluster_data(data,cluster_cnt,iter=20,thresh=1e-5):
    """ Group data into a number of common clusters

        data -- 2D array of data points.  Each point is a row in the array.
        cluster_cnt -- The number of clusters to use
        iter -- number of iterations to use for kmeans algorithm
        thresh -- distortion threshold for kmeans algorithm

        return -- list of 2D arrays.  Each array contains the data points
                  that belong to a specific cluster.

        Uses kmeans algorithm to find the clusters.
    """
    wh_data = vq.whiten(data)
    code_book,dist = vq.kmeans(wh_data,cluster_cnt,iter,thresh)
    code_ids, distortion = vq.vq(wh_data,code_book)
    clusters = []
    for i in range(len(code_book)):
        cluster = compress(code_ids == i,data,0)
        clusters.append(cluster)
    return clusters

if __name__ == "__main__":

    data = array(((400, 79, 5.4),
             (180, 76, 4.5),
             (28, 25, 30.),
             (270, 81, 5.0),
             (185, 78, 4.6)))

    clusters = cluster_data(data,2)
    for i in range(len(clusters)):
        print('cluster %d:' % i)
        print(clusters[i])