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Posted to commits@mahout.apache.org by sr...@apache.org on 2009/08/28 14:21:34 UTC
svn commit: r808858 - in
/lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model:
GenericItemPreferenceArray.java GenericUserPreferenceArray.java
Author: srowen
Date: Fri Aug 28 12:21:33 2009
New Revision: 808858
URL: http://svn.apache.org/viewvc?rev=808858&view=rev
Log:
Small sorting optimization since pref data is frequently already ordered.
Modified:
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericItemPreferenceArray.java
lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericUserPreferenceArray.java
Modified: lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericItemPreferenceArray.java
URL: http://svn.apache.org/viewvc/lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericItemPreferenceArray.java?rev=808858&r1=808857&r2=808858&view=diff
==============================================================================
--- lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericItemPreferenceArray.java (original)
+++ lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericItemPreferenceArray.java Fri Aug 28 12:21:33 2009
@@ -129,6 +129,16 @@
private void selectionSort(int type) {
// I think this sort will prove to be too dumb, but, it's in place and OK for tiny, mostly sorted data
int max = length();
+ boolean sorted = true;
+ for (int i = 1; i < max; i++) {
+ if (isLess(i, i-1, type)) {
+ sorted = false;
+ break;
+ }
+ }
+ if (sorted) {
+ return;
+ }
for (int i = 0; i < max; i++) {
int min = i;
for (int j = i + 1; j < max; j++) {
Modified: lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericUserPreferenceArray.java
URL: http://svn.apache.org/viewvc/lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericUserPreferenceArray.java?rev=808858&r1=808857&r2=808858&view=diff
==============================================================================
--- lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericUserPreferenceArray.java (original)
+++ lucene/mahout/trunk/core/src/main/java/org/apache/mahout/cf/taste/impl/model/GenericUserPreferenceArray.java Fri Aug 28 12:21:33 2009
@@ -130,6 +130,16 @@
private void selectionSort(int type) {
// I think this sort will prove to be too dumb, but, it's in place and OK for tiny, mostly sorted data
int max = length();
+ boolean sorted = true;
+ for (int i = 1; i < max; i++) {
+ if (isLess(i, i-1, type)) {
+ sorted = false;
+ break;
+ }
+ }
+ if (sorted) {
+ return;
+ }
for (int i = 0; i < max; i++) {
int min = i;
for (int j = i + 1; j < max; j++) {