In [1]:
import os
import numpy as np
import tensorflow as tf
import matplotlib.pyplot as plt
%matplotlib inline
print ("Packages loaded")
In [2]:
# Load them!
cwd = os.getcwd()
loadpath = cwd + "/data/custom_data.npz"
l = np.load(loadpath)
# See what's in here
print (l.files)
# Parse data
trainimg = l['trainimg']
trainlabel = l['trainlabel']
testimg = l['testimg']
testlabel = l['testlabel']
imgsize = l['imgsize']
ntrain = trainimg.shape[0]
nclass = trainlabel.shape[1]
dim = trainimg.shape[1]
ntest = testimg.shape[0]
print ("%d train images loaded" % (ntrain))
print ("%d test images loaded" % (ntest))
print ("%d dimensional input" % (dim))
print ("Image size is %s" % (imgsize))
print ("%d classes" % (nclass))
In [3]:
tf.set_random_seed(0)
# Parameters
learning_rate = 0.001
training_epochs = 200
batch_size = ntrain
display_step = 20
# Network Parameters
n_hidden_1 = 128 # 1st layer num features
n_hidden_2 = 128 # 2nd layer num features
n_input = dim # data input
n_classes = nclass # total classes (0-9 digits)
# tf Graph input
x = tf.placeholder("float", [None, n_input])
y = tf.placeholder("float", [None, n_classes])
# Create model
def multilayer_perceptron(_X, _weights, _biases):
layer_1 = tf.nn.relu(tf.add(tf.matmul(_X, _weights['h1']), _biases['b1']))
layer_2 = tf.nn.relu(tf.add(tf.matmul(layer_1, _weights['h2']), _biases['b2']))
return tf.matmul(layer_2, _weights['out']) + _biases['out']
# Store layers weight & bias
stddev = 0.1 # <== This greatly affects accuracy!!
weights = {
'h1': tf.Variable(tf.random_normal([n_input, n_hidden_1], stddev=stddev)),
'h2': tf.Variable(tf.random_normal([n_hidden_1, n_hidden_2], stddev=stddev)),
'out': tf.Variable(tf.random_normal([n_hidden_2, n_classes], stddev=stddev))
}
biases = {
'b1': tf.Variable(tf.random_normal([n_hidden_1])),
'b2': tf.Variable(tf.random_normal([n_hidden_2])),
'out': tf.Variable(tf.random_normal([n_classes]))
}
print ("Network Ready to Go!")
In [4]:
# Construct model
pred = multilayer_perceptron(x, weights, biases)
# Define loss and optimizer
cost = tf.reduce_mean(tf.nn.softmax_cross_entropy_with_logits(pred, y))
optm = tf.train.AdamOptimizer(learning_rate=learning_rate).minimize(cost)
corr = tf.equal(tf.argmax(pred, 1), tf.argmax(y, 1))
accr = tf.reduce_mean(tf.cast(corr, "float"))
# Initializing the variables
init = tf.initialize_all_variables()
print ("Functions ready")
In [5]:
# Launch the graph
sess = tf.Session()
sess.run(init)
# Training cycle
for epoch in range(training_epochs):
avg_cost = 0.
total_batch = int(ntrain/batch_size)
# Loop over all batches
for i in range(total_batch):
randidx = np.random.randint(ntrain, size=batch_size)
batch_xs = trainimg[randidx, :]
batch_ys = trainlabel[randidx, :]
# Fit training using batch data
sess.run(optm, feed_dict={x: batch_xs, y: batch_ys})
# Compute average loss
avg_cost += sess.run(cost,
feed_dict={x: batch_xs, y: batch_ys})/total_batch
# Display logs per epoch step
if epoch % display_step == 0:
print ("Epoch: %03d/%03d cost: %.9f" %
(epoch, training_epochs, avg_cost))
train_acc = sess.run(accr, feed_dict={x: batch_xs, y: batch_ys})
print (" Training accuracy: %.3f" % (train_acc))
test_acc = sess.run(accr, feed_dict={x: testimg, y: testlabel})
print (" Test accuracy: %.3f" % (test_acc))
print ("Optimization Finished!")
In [6]:
sess.close()
print ("Session closed.")