Daterset
import tensorflow as tf
import numpy as np
from tensorflow.contrib.data import Dataset
import matplotlib.pyplot as plt
# load your data or create your data in here
npx = np.random.uniform(-1, 1, (1000, 1)) # x data
npy = np.power(npx, 2) + np.random.normal(0, 0.1, size=npx.shape) # y data
npx_train, npx_test = np.split(npx, [800]) # training and test data
npy_train, npy_test = np.split(npy, [800])
# use placeholder, later you may need different data, pass the different data into placeholder
tfx = tf.placeholder(npx_train.dtype, npx_train.shape)
tfy = tf.placeholder(npy_train.dtype, npy_train.shape)
# create dataloader
dataset = tf.data.Dataset.from_tensor_slices((tfx, tfy))
dataset = dataset.shuffle(buffer_size=1000) # choose data randomly from this buffer
dataset = dataset.batch(32) # batch size you will use
dataset = dataset.repeat(3) # repeat for 3 epochs
iterator = dataset.make_initializable_iterator() # later we have to initialize this one
# your network
bx, by = iterator.get_next() # use batch to update
l1 = tf.layers.dense(bx, 10, tf.nn.relu)
out = tf.layers.dense(l1, npy.shape[1])
loss = tf.losses.mean_squared_error(by, out)
train = tf.train.GradientDescentOptimizer(0.1).minimize(loss)
sess = tf.Session()
# need to initialize the iterator in this case
sess.run([iterator.initializer, tf.global_variables_initializer()], feed_dict={tfx: npx_train, tfy: npy_train})
train_losses,test_losses=[],[]
for step in range(201):
try:
_, trainl = sess.run([train, loss]) # train
# if step % 10 == 0:
testl = sess.run(loss, {bx: npx_test, by: npy_test}) # test
train_losses.append(trainl)
test_losses.append(testl)
# print('step: %i/200' % step, '|train loss:', trainl, '|test loss:', testl)
except tf.errors.OutOfRangeError: # if training takes more than 3 epochs, training will be stopped
print('Finish the last epoch.')
break
print(step)
plt.plot(list(range(step)),train_losses,color='r',label='train loss')
plt.plot(list(range(step)),test_losses,color='b',label='test loss')
plt.legend(loc='best')
plt.show()
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