import gymnasium as gym from gymnasium import spaces import numpy as np from dataclasses import dataclass # here when we say "learner" we mean the agent that is learning to optimize the pricing and "agent" is part of the envrionment where the agent is creating demand that that "learner" is processing" @dataclass class BusinessLogicConstraints(): max_price_adjustment : float = 0.3 # maximum adjustment of price system_max_price : float = 500.0 # maximum price allowed in the system product_catelogue_size : int = 100 # number of products in the catalogue class PHANTOMEnv(gym.Env): def __init__(self): super(PHANTOMEnv, self).__init__() self.constraints = BusinessLogicConstraints() self.action_space = spaces.Box( low=-self.constraints.max_price_adjustment, high=self.constraints.max_price_adjustment, shape=(1,), dtype=np.float32) # we allow teh learner to adjust price by some BusinessLogicConstraints factor # Example for using image as input: self.observation_space = spaces.Dict({ 'elasticity': spaces.Dict({ 'price': spaces.Box(low=0, high=self.constraints.system_max_price, shape=(self.constraints.product_catelogue_size,), dtype=np.float32), 'demand': spaces.Box(low=0, high=np.inf, shape=(self.constraints.product_catelogue_size,), dtype=np.float32) }) }) def reset(self, seed=None, options=None): super().reset(seed=seed) # Initialize state self.state = { 'price': 100.0, # base price 'demand': 0.0 } return self.state, {} def step(self, action): # Apply action price_adjustment = action[0] new_price = self.state['price'] * (1 + price_adjustment) self.state['price'] = new_price # Simulate demand based on new price demand = self.simulate_demand(new_price) self.state['demand'] = demand # Calculate reward (e.g., revenue) reward = new_price * demand # Check if episode is done done = self.state['price'] <= 0.0 or self.state['demand'] <= 0.0 return self.state, reward, done, False, {} def simulate_demand(self, price): # Simple linear demand model: demand decreases as price increases base_demand = 200 price_sensitivity = 0.5 demand = max(0, base_demand - price_sensitivity * price) return demand if __name__ == "__main__": env = PHANTOMEnv() obs, _ = env.reset() done = False total_reward = 0 while not done: action = env.action_space.sample() # Random action obs, reward, done, _, _ = env.step(action) total_reward += reward print(f"Price: {obs['price']:.2f}, Demand: {obs['demand']:.2f}, Reward: {reward:.2f}") if done: break print(f"Total Reward: {total_reward:.2f}")