new class for reward functions

python/rewardFunctions/linearRewardFunction.py

+from rewardFunctions.rewardFunction import RewardFunction
+
+class LinearRewardFunction(RewardFunction):
+    def __init__(self, weights):
+        self.setParameters(weights)
+
+    def setParameters(self, parameters):
+        self.weights = parameters
+
+    def getReward(self, features):
+        reward = self.weights.dot(features)

python/rewardFunctions/rewardFunction.py

+class RewardFunction():
+    def getReward(self, features):
+        raise NotImplementedError( "RewardFunction does not provide getReward(self, features)" )
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