Author: srowen
Date: Tue Dec 30 07:37:00 2008
New Revision: 730155
URL: http://svn.apache.org/viewvc?rev=730155&view=rev
Log: (empty)
Added:
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericPreferenceArray.java
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/model/PreferenceArray.java
Added:
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericPreferenceArray.java
URL:
http://svn.apache.org/viewvc/lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericPreferenceArray.java?rev=730155&view=auto
==============================================================================
---
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericPreferenceArray.java
(added)
+++
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericPreferenceArray.java
Tue Dec 30 07:37:00 2008
@@ -0,0 +1,90 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.mahout.cf.taste.impl.model;
+
+import org.apache.mahout.cf.taste.model.Item;
+import org.apache.mahout.cf.taste.model.Preference;
+import org.apache.mahout.cf.taste.model.User;
+import org.apache.mahout.cf.taste.model.PreferenceArray;
+
+import java.io.Serializable;
+
+/**
+ * This implementation maintains three parallel arrays, of {...@link User}s,
{...@link Item}s, and values.
+ * The idea is to save allocating {...@link Preference} objects themselves.
+ * On a 64-bit virtual machine, this should save 12 bytes per element (the
overhead of an
+ * enclosing {...@link Preference} object reference and object header).
+ *
+ * This is not used yet.
+ */
+public final class GenericPreferenceArray implements PreferenceArray,
Serializable {
+
+ private final User[] users;
+ private final Item[] items;
+ private final double[] values;
+
+ public GenericPreferenceArray(int size) {
+ users = new User[size];
+ items = new Item[size];
+ values = new double[size];
+ }
+
+ @Override
+ public Preference get(int i) {
+ return new GenericPreference(users[i], items[i], values[i]);
+ }
+
+ @Override
+ public void set(int i, Preference pref) {
+ users[i] = pref.getUser();
+ items[i] = pref.getItem();
+ values[i] = pref.getValue();
+ }
+
+ @Override
+ public User getUser(int i) {
+ return users[i];
+ }
+
+ @Override
+ public void setUser(int i, User user) {
+ users[i] = user;
+ }
+
+ @Override
+ public Item getItem(int i) {
+ return items[i];
+ }
+
+ @Override
+ public void setItem(int i, Item item) {
+ items[i] = item;
+ }
+
+
+ @Override
+ public double getValue(int i) {
+ return values[i];
+ }
+
+ @Override
+ public void setValue(int i, double value) {
+ values[i] = value;
+ }
+
+}
\ No newline at end of file
Added:
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/model/PreferenceArray.java
URL:
http://svn.apache.org/viewvc/lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/model/PreferenceArray.java?rev=730155&view=auto
==============================================================================
---
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/model/PreferenceArray.java
(added)
+++
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/model/PreferenceArray.java
Tue Dec 30 07:37:00 2008
@@ -0,0 +1,42 @@
+/**
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You under the Apache License, Version 2.0
+ * (the "License"); you may not use this file except in compliance with
+ * the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.apache.mahout.cf.taste.model;
+
+/**
+ * An alternate representation of an array of {...@link Preference}.
Implementations, in theory,
+ * can produce a more memory-efficient representation. This is not used yet.
+ */
+public interface PreferenceArray {
+
+ Preference get(int i);
+
+ void set(int i, Preference pref);
+
+ User getUser(int i);
+
+ void setUser(int i, User user);
+
+ Item getItem(int i);
+
+ void setItem(int i, Item item);
+
+ double getValue(int i);
+
+ void setValue(int i, double value);
+
+}
\ No newline at end of file
