test.py

# -*- coding: utf-8 -*-
"""
Created on Thu Feb 25 16:09:58 2016
Test MNIST dataset 
@author: liudiwei
"""

from sklearn import neighbors  
from data_util import DataUtils
import datetime  


def main():
    trainfile_X = '../dataset/MNIST/train-images.idx3-ubyte'
    trainfile_y = '../dataset/MNIST/train-labels.idx1-ubyte'
    testfile_X = '../dataset/MNIST/t10k-images.idx3-ubyte'
    testfile_y = '../dataset/MNIST/t10k-labels.idx1-ubyte'
    train_X = DataUtils(filename=trainfile_X).getImage()
    train_y = DataUtils(filename=trainfile_y).getLabel()
    test_X = DataUtils(testfile_X).getImage()
    test_y = DataUtils(testfile_y).getLabel()

    return train_X, train_y, test_X, test_y 


def testKNN():
    train_X, train_y, test_X, test_y = main()
    startTime = datetime.datetime.now()
    knn = neighbors.KNeighborsClassifier(n_neighbors=3)  
    knn.fit(train_X, train_y)  
    match = 0;  
    for i in xrange(len(test_y)):  
        predictLabel = knn.predict(test_X[i])[0]  
        if(predictLabel==test_y[i]):  
            match += 1  
      
    endTime = datetime.datetime.now()  
    print 'use time: '+str(endTime-startTime)  
    print 'error rate: '+ str(1-(match*1.0/len(test_y)))  

if __name__ == "__main__":
    testKNN()