Merge pull request #39 from kris7t/partial-interpretation

Implement partial interpretation based model generation

1 files changed, 48 insertions, 0 deletions

diff --git a/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/Accuracy.java b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/Accuracy.java
new file mode 100644
index 00000000..338990ab
--- /dev/null
+++ b/subprojects/viatra-runtime/src/main/java/tools/refinery/viatra/runtime/matchers/util/Accuracy.java
@@ -0,0 +1,48 @@
+/*******************************************************************************
+ * Copyright (c) 2010-2018, Gabor Bergmann, IncQuery Labs Ltd.
+ * This program and the accompanying materials are made available under the
+ * terms of the Eclipse Public License v. 2.0 which is available at
+ * http://www.eclipse.org/legal/epl-v20.html.
+ * 
+ * SPDX-License-Identifier: EPL-2.0
+ *******************************************************************************/
+package tools.refinery.viatra.runtime.matchers.util;
+
+/**
+ * The degree of accuracy of a cardinality estimate
+ * @author Gabor Bergmann
+ * @since 2.1
+ */
+public enum Accuracy {
+    EXACT_COUNT,
+    BEST_UPPER_BOUND,
+    BEST_LOWER_BOUND,
+    APPROXIMATION;
+    
+    /**
+     * Partial order comparison.
+     */
+    public boolean atLeastAsPreciseAs(Accuracy other) {
+        switch (this) {
+        case EXACT_COUNT: return true;
+        case APPROXIMATION: return APPROXIMATION == other;
+        case BEST_UPPER_BOUND: return BEST_UPPER_BOUND == other || APPROXIMATION == other; 
+        case BEST_LOWER_BOUND: return BEST_LOWER_BOUND == other || APPROXIMATION == other; 
+        default: throw new IllegalArgumentException();
+        }
+    }
+    
+    /**
+     * @return another accuracy value that is anti-monotonic to this one, 
+     * i.e. an accuracy that should be used in the denominator to obtain a fraction with this accuracy
+     */
+    public Accuracy reciprocal() {
+        switch(this) {
+        case APPROXIMATION: return APPROXIMATION;
+        case BEST_UPPER_BOUND: return BEST_LOWER_BOUND;
+        case BEST_LOWER_BOUND: return BEST_UPPER_BOUND;
+        case EXACT_COUNT: return EXACT_COUNT;
+        default: throw new IllegalArgumentException();
+        }
+    }
+}