Example #1
0
File: ves.py Project: avain/pybrain
    def _batchLearn(self):
        """ Batch learning. """
        xdim = self.numParameters
        # produce samples and evaluate them
        try:
            self._produceSamples()

            # shape their fitnesses
            shapedFits = self.shapingFunction(self.allFitnesses[-self.batchSize :])

            # update parameters (unbiased: divide by batchsize)
            update = self._calcBatchUpdate(shapedFits)
            if self.elitism:
                self.x = self.bestEvaluable
            else:
                self.x += self.learningRate * update[:xdim]
            self.factorSigma += self.learningRateSigma * flat2triu(update[xdim:], xdim)
            self.sigma = dot(self.factorSigma.T, self.factorSigma)

        except ValueError:
            print("Numerical Instability. Stopping.")
            self.maxLearningSteps = self.numLearningSteps

        if self._hasConverged():
            print("Premature convergence. Stopping.")
            self.maxLearningSteps = self.numLearningSteps

        if self.verbose:
            print("Evals:", self.numEvaluations)

        self.allCenters.append(self.x.copy())
        self.allFactorSigmas.append(self.factorSigma.copy())

        if self.storeAllDistributions:
            self._allDistributions.append((self.x.copy(), self.sigma.copy()))
Example #2
0
File: ves.py Project: HKou/pybrain
 def _batchLearn(self, maxSteps):
     """ Batch learning. """
     while (self.evalsDone < maxSteps 
            and not self.bestEvaluation >= self.desiredEvaluation):
         # produce samples and evaluate them        
         try:
             self._produceSamples()
             
             # shape their fitnesses
             shapedFits = self.shapingFunction(self.allFitnesses[-self.batchSize:])
         
             # update parameters (unbiased: divide by batchsize)
             update = self._calcBatchUpdate(shapedFits) 
             if self.elitism:
                 self.x = self.bestEvaluable
             else:
                 self.x += self.learningRate * update[:self.xdim]
             self.factorSigma += self.learningRateSigma * flat2triu(update[self.xdim:], self.xdim)
             self.sigma = dot(self.factorSigma.T, self.factorSigma)
         
         except ValueError:
             print 'Numerical Instability. Stopping.'
             break
         
         if self._hasConverged():
             print 'Premature convergence. Stopping.'
             break
         
         if self.verbose:
             print 'G:', self.generation, 'Evals:', self.evalsDone, 'MaxG:', max(self.allFitnesses[-self.batchSize:])
             
         self.allCenters.append(self.x.copy())
         self.allFactorSigmas.append(self.factorSigma.copy())
         self.generation += 1
Example #3
0
    def _batchLearn(self):
        """ Batch learning. """
        xdim = self.numParameters
        # produce samples and evaluate them
        try:
            self._produceSamples()

            # shape their fitnesses
            shapedFits = self.shapingFunction(
                self.allFitnesses[-self.batchSize:])

            # update parameters (unbiased: divide by batchsize)
            update = self._calcBatchUpdate(shapedFits)
            if self.elitism:
                self.x = self.bestEvaluable
            else:
                self.x += self.learningRate * update[:xdim]
            self.factorSigma += self.learningRateSigma * flat2triu(
                update[xdim:], xdim)
            self.sigma = dot(self.factorSigma.T, self.factorSigma)

        except ValueError:
            print 'Numerical Instability. Stopping.'
            self.maxLearningSteps = self.numLearningSteps

        if self._hasConverged():
            print 'Premature convergence. Stopping.'
            self.maxLearningSteps = self.numLearningSteps

        if self.verbose:
            print 'Evals:', self.numEvaluations,

        self.allCenters.append(self.x.copy())
        self.allFactorSigmas.append(self.factorSigma.copy())
Example #4
0
    def _onlineLearn(self):
        """ Online learning. """
        # produce one sample and evaluate
        xdim = self.numParameters
        self._produceNewSample()
        if len(self.allSamples) <= self.batchSize:
            return

        # shape the fitnesses of the last samples
        shapedFits = self.shapingFunction(self.allFitnesses[-self.batchSize :])

        # update parameters
        update = self._calcOnlineUpdate(shapedFits)
        self.x += self.learningRate * update[:xdim]
        self.factorSigma += self.learningRateSigma * flat2triu(update[xdim:], xdim)
        self.sigma = dot(self.factorSigma.T, self.factorSigma)
Example #5
0
    def _onlineLearn(self):
        """ Online learning. """
        # produce one sample and evaluate
        xdim = self.numParameters
        self._produceNewSample()
        if len(self.allSamples) <= self.batchSize:
            return

        # shape the fitnesses of the last samples
        shapedFits = self.shapingFunction(self.allFitnesses[-self.batchSize:])

        # update parameters
        update = self._calcOnlineUpdate(shapedFits)
        self.x += self.learningRate * update[:xdim]
        self.factorSigma += self.learningRateSigma * flat2triu(
            update[xdim:], xdim)
        self.sigma = dot(self.factorSigma.T, self.factorSigma)
Example #6
0
    def _batchLearn(self, maxSteps):
        """ Batch learning. """
        while (self.evalsDone < maxSteps
               and not self.bestEvaluation >= self.desiredEvaluation):
            # produce samples and evaluate them
            try:
                self._produceSamples()

                # shape their fitnesses
                shapedFits = self.shapingFunction(
                    self.allFitnesses[-self.batchSize:])

                # update parameters (unbiased: divide by batchsize)
                update = self._calcBatchUpdate(shapedFits)
                if self.elitism:
                    self.x = self.bestEvaluable
                else:
                    self.x += self.learningRate * update[:self.xdim]
                self.factorSigma += self.learningRateSigma * flat2triu(
                    update[self.xdim:], self.xdim)
                self.sigma = dot(self.factorSigma.T, self.factorSigma)

            except ValueError:
                print 'Numerical Instability. Stopping.'
                break

            if self._hasConverged():
                print 'Premature convergence. Stopping.'
                break

            if self.verbose:
                print 'G:', self.generation, 'Evals:', self.evalsDone, 'MaxG:', max(
                    self.allFitnesses[-self.batchSize:])

            self.allCenters.append(self.x.copy())
            self.allFactorSigmas.append(self.factorSigma.copy())
            self.generation += 1