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@DollarAkshay
Last active December 20, 2016 07:58
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Acrobot v1 using Genetic Algorithm and Neural Netowks
import time, math, random, bisect, copy
import gym
import numpy as np
class NeuralNet :
def __init__(self, nodeCount):
self.fitness = 0
self.nodeCount = nodeCount
self.weights = []
self.biases = []
for i in range(len(nodeCount) - 1):
self.weights.append( np.random.uniform(low=-1, high=1, size=(nodeCount[i], nodeCount[i+1])).tolist() )
self.biases.append( np.random.uniform(low=-1, high=1, size=(nodeCount[i+1])).tolist())
def printWeightsandBiases(self):
print("--------------------------------")
print("Weights :\n[", end="")
for i in range(len(self.weights)):
print("\n [ ", end="")
for j in range(len(self.weights[i])):
if j!=0:
print("\n ", end="")
print("[", end="")
for k in range(len(self.weights[i][j])):
print(" %5.2f," % (self.weights[i][j][k]), end="")
print("\b],", end="")
print("\b ],")
print("\n]")
print("\nBiases :\n[", end="")
for i in range(len(self.biases)):
print("\n [ ", end="")
for j in range(len(self.biases[i])):
print(" %5.2f," % (self.biases[i][j]), end="")
print("\b],", end="")
print("\b \n]\n--------------------------------\n")
def getOutput(self, input):
output = input
for i in range(len(self.nodeCount)-1):
output = np.reshape( np.matmul(output, self.weights[i]) + self.biases[i], (self.nodeCount[i+1]))
return np.argmax(sigmoid(output))
class Population :
def __init__(self, populationCount, mutationRate, nodeCount):
self.nodeCount = nodeCount
self.popCount = populationCount
self.m_rate = mutationRate
self.population = [ NeuralNet(nodeCount) for i in range(populationCount)]
def createChild(self, nn1, nn2):
child = NeuralNet(self.nodeCount)
for i in range(len(child.weights)):
for j in range(len(child.weights[i])):
for k in range(len(child.weights[i][j])):
if random.random() > self.m_rate:
child.weights[i][j][k] = (nn1.weights[i][j][k] + nn2.weights[i][j][k])/2.0
for i in range(len(child.biases)):
for j in range(len(child.biases[i])):
if random.random() > self.m_rate:
child.biases[i][j] = (nn1.biases[i][j] + nn2.biases[i][j])/2.0
return child
def createNewGeneration(self, bestNN):
nextGen = []
nextGen.append(copy.deepcopy(bestNN))
fitnessSum = [0]
for i in range(len(self.population)):
fitnessSum.append(fitnessSum[i]+self.population[i].fitness**3)
while(len(nextGen) < self.popCount):
r1 = random.uniform(0, fitnessSum[len(fitnessSum)-1] )
r2 = random.uniform(0, fitnessSum[len(fitnessSum)-1] )
nn1 = self.population[bisect.bisect_right(fitnessSum, r1)-1]
nn2 = self.population[bisect.bisect_right(fitnessSum, r2)-1]
nextGen.append( self.createChild(nn1, nn2) )
self.population.clear()
self.population = nextGen
def sigmoid(x):
return 1.0/(1.0 + np.exp(-x))
def replayBestBots(bestNeuralNets, steps, sleep):
for i in range(len(bestNeuralNets)):
if i%steps == 0 :
observation = env.reset()
print("Generation %3d had a best fitness of %4d" % (i, bestNeuralNets[i].fitness))
for step in range(MAX_STEPS):
env.render()
time.sleep(sleep)
observation = normalizeArray( observation, obsMin, obsMax)
action = nn.getOutput(observation)
observation, reward, done, info = env.step(action)
if done:
break
print("Steps taken =", step)
def uploadSimulation():
choice = input("\nDo you want to upload the simulation ?[Y/N] : ")
if choice=='Y' or choice=='y':
partialKey = input("\nEnter last 2 characters of API Key : ")
gym.upload('Artificial Intelligence/'+GAME, api_key='sk_pwRfoNpISVKq3o88csB'+partialKey)
def mapRange(value, leftMin, leftMax, rightMin, rightMax):
# Figure out how 'wide' each range is
leftSpan = leftMax - leftMin
rightSpan = rightMax - rightMin
# Convert the left range into a 0-1 range (float)
valueScaled = float(value - leftMin) / float(leftSpan)
# Convert the 0-1 range into a value in the right range.
return rightMin + (valueScaled * rightSpan)
def normalizeArray(aVal, aMin, aMax):
res = []
for i in range(len(aVal)):
res.append( mapRange(aVal[i], aMin[i], aMax[i], -1, 1) )
return res
def scaleArray(aVal, aMin, aMax):
res = []
for i in range(len(aVal)):
res.append( mapRange(aVal[i], -1, 1, aMin[i], aMax[i]) )
return res
GAME = 'Acrobot-v1'
RECORD = None
MAX_STEPS = 500
MIN_REWARD = -1
MAX_REWARD = 0
MAX_GENERATIONS = 50
POPULATION_COUNT = 50
MUTATION_RATE = 0.01
env = gym.make(GAME)
env.monitor.start('Artificial Intelligence/'+GAME, force=True, video_callable=RECORD )
observation = env.reset()
in_dimen = env.observation_space.shape[0]
out_dimen = env.action_space.n
obsMin = env.observation_space.low
obsMax = env.observation_space.high
actionMin = 0
actionMax = env.action_space.n
pop = Population(POPULATION_COUNT, MUTATION_RATE, [in_dimen, 8, 5, out_dimen])
bestNeuralNets = []
print("\nObservation\n--------------------------------")
print("Shape :", in_dimen, " | High :", obsMax, " | Low :", obsMin)
print("\nAction\n--------------------------------")
print("Shape :", out_dimen, " | High :", actionMax, " | Low :", actionMin,"\n")
for gen in range(MAX_GENERATIONS):
genAvgFit = 0.0
maxFit = 0.0
maxNeuralNet = None
for nn in pop.population:
for step in range(MAX_STEPS):
env.render()
observation = normalizeArray( observation, obsMin, obsMax)
action = nn.getOutput(observation)
observation, reward, done, info = env.step(action)
if done:
observation = env.reset()
break
nn.fitness = 100.0*(MAX_STEPS-step)/MAX_STEPS
genAvgFit += nn.fitness
if nn.fitness > maxFit :
maxFit = nn.fitness
maxNeuralNet = copy.deepcopy(nn);
bestNeuralNets.append(maxNeuralNet)
genAvgFit/=pop.popCount
print("Generation : %3d | Avg Fitness : %4.0f | Max Fitness : %4.0f " % (gen+1, genAvgFit, maxFit) )
pop.createNewGeneration(maxNeuralNet)
env.monitor.close()
uploadSimulation()
choice = input("Do you want to watch the replay ?[Y/N] : ")
if choice=='Y' or choice=='y':
replayBestBots(bestNeuralNets, max(1, int(math.ceil(MAX_GENERATIONS/10.0))), 0.0625)
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