Naming tweak

Skills/TrueSkill/Factors/GaussianFactor.php

@@ -0,0 +1,45 @@
+<?php
+
+namespace Moserware\Skills\TrueSkill\Factors;
+
+require_once(dirname(__FILE__) . "/../../FactorGraphs/Factor.php");
+require_once(dirname(__FILE__) . "/../../FactorGraphs/Message.php");
+require_once(dirname(__FILE__) . "/../../FactorGraphs/Variable.php");
+require_once(dirname(__FILE__) . "/../../Numerics/GaussianDistribution.php");
+
+use Moserware\Numerics\GaussianDistribution;
+use Moserware\Skills\FactorGraphs\Factor;
+use Moserware\Skills\FactorGraphs\Message;
+use Moserware\Skills\FactorGraphs\Variable;
+
+abstract class GaussianFactor extends Factor
+{
+    protected function __construct($name)
+    {
+        parent::__construct($name);
+    }
+
+    /**
+     * Sends the factor-graph message with and returns the log-normalization constant.
+     */
+    protected function sendMessageVariable(Message &$message, Variable &$variable)
+    {
+        $marginal = &$variable->getValue();
+        $messageValue = &$message->getValue();
+        $logZ = GaussianDistribution::logProductNormalization($marginal, $messageValue);
+        $variable->setValue(GaussianDistribution::multiply($marginal, $messageValue));
+        return $logZ;
+    }
+
+    public function &createVariableToMessageBinding(Variable &$variable)
+    {
+        $newDistribution = GaussianDistribution::fromPrecisionMean(0, 0);
+        $binding = &parent::createVariableToMessageBindingWithMessage($variable,
+                                                      new Message(
+                                                          $newDistribution,
+                                                          sprintf("message from %s to %s", $this, $variable)));
+        return $binding;
+    }
+}
+
+?>