diff --git a/Machine_Learning_Algorithms/Proximal Policy Optimization (PPO)Algorithm /Program.c b/Machine_Learning_Algorithms/Proximal Policy Optimization (PPO)Algorithm /Program.c new file mode 100644 index 00000000..be24f25e --- /dev/null +++ b/Machine_Learning_Algorithms/Proximal Policy Optimization (PPO)Algorithm /Program.c @@ -0,0 +1,81 @@ +#include +#include +#include + +#define TRAJECTORY_LENGTH 100 +#define NUM_TRAJECTORIES 10 +#define CLIP_EPSILON 0.2 +#define LEARNING_RATE 0.001 +#define GAMMA 0.99 +#define LAMBDA 0.95 + +// Placeholder functions for the neural network +double policy(double state) { + // Simple placeholder function for policy + return state * 0.1; +} + +double value_function(double state) { + // Simple placeholder function for value function + return state * 0.5; +} + +// Calculate advantage function using Generalized Advantage Estimation (GAE) +double calculate_advantage(double rewards[], double values[], int t) { + double advantage = 0.0; + double discount = 1.0; + for (int k = t; k < TRAJECTORY_LENGTH; ++k) { + advantage += discount * (rewards[k] + GAMMA * values[k + 1] - values[k]); + discount *= GAMMA * LAMBDA; + } + return advantage; +} + +// Policy update with clipping +double clipped_objective(double ratio, double advantage) { + double clip_value = fmax(1 - CLIP_EPSILON, fmin(1 + CLIP_EPSILON, ratio)); + return fmin(ratio * advantage, clip_value * advantage); +} + +// Main PPO loop +void PPO() { + double states[TRAJECTORY_LENGTH]; + double actions[TRAJECTORY_LENGTH]; + double rewards[TRAJECTORY_LENGTH]; + double values[TRAJECTORY_LENGTH]; + double advantages[TRAJECTORY_LENGTH]; + double returns[TRAJECTORY_LENGTH]; + + for (int episode = 0; episode < NUM_TRAJECTORIES; ++episode) { + // Simulate data collection + for (int t = 0; t < TRAJECTORY_LENGTH; ++t) { + states[t] = (double)t; // Placeholder state + actions[t] = policy(states[t]); // Take action according to policy + rewards[t] = -fabs(actions[t]); // Placeholder reward function + values[t] = value_function(states[t]); + } + + // Calculate returns and advantages + for (int t = 0; t < TRAJECTORY_LENGTH; ++t) { + returns[t] = rewards[t] + GAMMA * values[t + 1]; + advantages[t] = calculate_advantage(rewards, values, t); + } + + // Update policy using clipped objective + for (int t = 0; t < TRAJECTORY_LENGTH; ++t) { + double old_policy = policy(states[t]); + double ratio = policy(states[t]) / old_policy; // Placeholder policy ratio + double objective = clipped_objective(ratio, advantages[t]); + + // Simple gradient update (mock update, as no neural network here) + // In practice, we would use neural network gradients + double policy_update = LEARNING_RATE * objective; + printf("Policy updated for state %f with value %f\n", states[t], policy_update); + } + } +} + +int main() { + PPO(); + return 0; +}