[tune] Directional metrics for components (#4120) (#4915)

python/ray/tune/examples/sigopt_example.py

@@ -18,8 +18,7 @@ def easy_objective(config, reporter):
     for i in range(config["iterations"]):
         reporter(
             timesteps_total=i,
-            neg_mean_loss=-(config["height"] - 14)**2 +
-            abs(config["width"] - 3))
+            mean_loss=(config["height"] - 14)**2 - abs(config["width"] - 3))
         time.sleep(0.02)
 
 
@@ -68,8 +67,9 @@ if __name__ == "__main__":
         space,
         name="SigOpt Example Experiment",
         max_concurrent=1,
-        reward_attr="neg_mean_loss")
-    scheduler = AsyncHyperBandScheduler(reward_attr="neg_mean_loss")
+        metric="mean_loss",
+        mode="min")
+    scheduler = AsyncHyperBandScheduler(metric="mean_loss", mode="min")
     run(easy_objective,
         name="my_exp",
         search_alg=algo,