Fix bug in Exponential score function.

Closes probmods#883.
v1ta111 · Sep 25, 2017 · 6320c21 · 6320c21
1 parent 220b948
commit 6320c21
Showing 1 changed file with 3 additions and 1 deletion.
diff --git a/src/dists/exponential.ad.js b/src/dists/exponential.ad.js
@@ -18,7 +18,9 @@ var Exponential = base.makeDistributionType({
   },
   score: function(val) {
     'use ad';
-    return Math.log(this.params.a) - this.params.a * val;
+    return val >= 0 ?
+      Math.log(this.params.a) - this.params.a * val :
+      -Infinity;
   },
   base: function() {
     return new Uniform({a: 0, b: 1});