diff simple_autoassociator.py/main.py @ 386:a474341861fa

Added a simple AA
author Joseph Turian <turian@gmail.com>
date Tue, 08 Jul 2008 02:27:00 -0400
parents sparse_random_autoassociator/main.py@e4473d9697d7
children 98ca97cc9910
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line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/simple_autoassociator.py/main.py	Tue Jul 08 02:27:00 2008 -0400
@@ -0,0 +1,31 @@
+#!/usr/bin/python
+"""
+    A simple autoassociator.
+
+    The learned model is::
+       h   = sigmoid(dot(x, w1) + b1)
+       y   = sigmoid(dot(h, w2) + b2)
+
+    Binary xent loss.
+
+    LIMITATIONS:
+       - Only does pure stochastic gradient (batchsize = 1).
+"""
+
+
+import numpy
+
+nonzero_instances = []
+nonzero_instances.append({1: 0.1, 5: 0.5, 9: 1})
+nonzero_instances.append({2: 0.3, 5: 0.5, 8: 0.8})
+nonzero_instances.append({1: 0.2, 2: 0.3, 5: 0.5})
+
+import model
+model = model.Model()
+
+for i in xrange(100000):
+    # Select an instance
+    instance = nonzero_instances[i % len(nonzero_instances)]
+
+    # SGD update over instance
+    model.update(instance)