tron: fix trial value in linesearch

dpo · dpo · commit bdc31814c24e · 2016-10-15T12:00:19.000-04:00
Closes PythonOptimizers#59
diff --git a/nlp/optimize/tron.py b/nlp/optimize/tron.py
@@ -485,7 +485,7 @@ def solve(self):
                     for step in ls:
                         self.log.debug(ls_fmt, step, ls.trial_value)
 
-                    ared = self.f - f_trial
+                    ared = self.f - ls.trial_value
                     self.x = ls.iterate
                     self.f = ls.trial_value
                     self.g = model.grad(self.x)
