fix: reset grace when init score changes

TimefoldAI · Jan 16, 2025 · 1294d64 · 1294d64
1 parent 2c0f1e1
commit 1294d64
Show file tree

Hide file tree

Showing 2 changed files with 75 additions and 0 deletions.
diff --git a/core/src/main/java/ai/timefold/solver/core/impl/solver/termination/AdaptiveTermination.java b/core/src/main/java/ai/timefold/solver/core/impl/solver/termination/AdaptiveTermination.java
@@ -55,6 +55,10 @@ private static <Score_ extends Score<Score_>> double softImprovementOrNaNForHard
             // vast majority of comparisons
             return 0.0;
         }
+        if (start.initScore() != end.initScore()) {
+            // init score improved
+            return Double.NaN;
+        }
         var scoreDiffs = end.subtract(start).toLevelDoubles();
         var softestLevel = scoreDiffs.length - 1;
         for (int i = 0; i < softestLevel; i++) {

diff --git a/...rc/test/java/ai/timefold/solver/core/impl/solver/termination/AdaptiveTerminationTest.java b/...rc/test/java/ai/timefold/solver/core/impl/solver/termination/AdaptiveTerminationTest.java
@@ -72,6 +72,49 @@ void testTerminatesWhenImprovementDoesNotMeetCriteria() {
         assertThat(termination.isTerminated(31 * NANOS_PER_MILLISECOND, score)).isTrue();
     }
 
+    @Test
+    void testImprovementInInitScoreResetsGrace() {
+        var termination = new AdaptiveTermination<Object, SimpleScore>(10, 1);
+
+        var score = SimpleScore.ofUninitialized(-1, 0);
+        termination.start(0L, score);
+
+        score = SimpleScore.ofUninitialized(-1, 1);
+        assertThat(termination.isTerminated(10 * NANOS_PER_MILLISECOND, score)).isFalse();
+        // Y_0 is 1 - 0 = 1
+
+        score = SimpleScore.ofUninitialized(-1, 2);
+        termination.step(11 * NANOS_PER_MILLISECOND, score);
+
+        // These will compare as 2 - 1 = 1, 1 / 1 >= 1
+        assertThat(termination.isTerminated(11 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(12 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(15 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(19 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(20 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        score = SimpleScore.of(2);
+        termination.step(21 * NANOS_PER_MILLISECOND, score);
+
+        // This will reset the grace period
+        assertThat(termination.isTerminated(21 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(30 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        score = SimpleScore.of(4);
+        termination.step(31 * NANOS_PER_MILLISECOND, score);
+
+        // Y_0 is 4 - 2 = 2
+
+        // These will compare as 4 - 2 = 2, 2 / 2 >= 1
+        assertThat(termination.isTerminated(31 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(40 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        score = SimpleScore.of(5);
+        termination.step(31 * NANOS_PER_MILLISECOND, score);
+        // This will compare as 5 - 4 = 1, 1 / 2 < 1, so terminate
+        assertThat(termination.isTerminated(41 * NANOS_PER_MILLISECOND, score)).isTrue();
+    }
+
     @Test
     void testImprovementInHardScoreResetsGrace() {
         var termination = new AdaptiveTermination<Object, HardSoftScore>(10, 1);
@@ -142,4 +185,32 @@ void testImprovementInHardScoreDuringGrace() {
         // These will compare as 1 - 0 = 1, 1 / 2 < 2, so terminate
         assertThat(termination.isTerminated(20 * NANOS_PER_MILLISECOND, score)).isTrue();
     }
+
+    @Test
+    void testImprovementInInitScoreDuringGrace() {
+        var termination = new AdaptiveTermination<Object, SimpleScore>(10, 1);
+
+        var score = SimpleScore.ofUninitialized(-1, 0);
+        termination.start(0, score);
+
+        score = SimpleScore.of(-1);
+        termination.step(5 * NANOS_PER_MILLISECOND, score);
+        assertThat(termination.isTerminated(5 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        score = SimpleScore.of(0);
+        termination.step(10 * NANOS_PER_MILLISECOND, score);
+        assertThat(termination.isTerminated(10 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        score = SimpleScore.of(1);
+        termination.step(15 * NANOS_PER_MILLISECOND, score);
+        assertThat(termination.isTerminated(15 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        // Y_0 is 1 - (-1) = 2
+        // These will compare as 1 - (-1) = 2, 2 / 2 >= 2
+        assertThat(termination.isTerminated(16 * NANOS_PER_MILLISECOND, score)).isFalse();
+        assertThat(termination.isTerminated(19 * NANOS_PER_MILLISECOND, score)).isFalse();
+
+        // These will compare as 1 - 0 = 1, 1 / 2 < 2, so terminate
+        assertThat(termination.isTerminated(20 * NANOS_PER_MILLISECOND, score)).isTrue();
+    }
 }