tensorflow实现KNN识别MNIST

__author__ = 'freedom' import tensorflow as tf import numpy as np  def loadMNIST():  from tensorflow.examples.tutorials.mnist import input_data  mnist = input_data.read_data_sets('MNIST_data',one_hot=True)  return mnist def KNN(mnist):  train_x,train_y = mnist.train.next_batch(5000)  test_x,test_y = mnist.train.next_batch(200)   xtr = tf.placeholder(tf.float32,[None,784])  xte = tf.placeholder(tf.float32,[784])  distance = tf.sqrt(tf.reduce_sum(tf.pow(tf.add(xtr,tf.neg(xte)),2),reduction_indices=1))   pred = tf.argmin(distance,0)   init = tf.initialize_all_variables()   sess = tf.Session()  sess.run(init)   right = 0  for i in range(200):   ansIndex = sess.run(pred,{xtr:train_x,xte:test_x[i,:]})   print 'prediction is ',np.argmax(train_y[ansIndex])   print 'true value is ',np.argmax(test_y[i])   if np.argmax(test_y[i]) == np.argmax(train_y[ansIndex]):    right += 1.0  accracy = right/200.0  print accracy  if __name__ == "__main__":  mnist = loadMNIST()  KNN(mnist)