pmlpp/mlpp/probit_reg/probit_reg.cpp

246 lines
7.2 KiB
C++

//
// ProbitReg.cpp
//
// Created by Marc Melikyan on 10/2/20.
//
#include "probit_reg.h"
#include "../activation/activation.h"
#include "../cost/cost.h"
#include "../lin_alg/lin_alg.h"
#include "../regularization/reg.h"
#include "../utilities/utilities.h"
#include <iostream>
#include <random>
MLPPProbitReg::MLPPProbitReg(std::vector<std::vector<double>> inputSet, std::vector<double> outputSet, std::string reg, double lambda, double alpha) :
inputSet(inputSet), outputSet(outputSet), n(inputSet.size()), k(inputSet[0].size()), reg(reg), lambda(lambda), alpha(alpha) {
y_hat.resize(n);
weights = MLPPUtilities::weightInitialization(k);
bias = MLPPUtilities::biasInitialization();
}
std::vector<double> MLPPProbitReg::modelSetTest(std::vector<std::vector<double>> X) {
return Evaluate(X);
}
double MLPPProbitReg::modelTest(std::vector<double> x) {
return Evaluate(x);
}
void MLPPProbitReg::gradientDescent(double learning_rate, int max_epoch, bool UI) {
MLPPActivation avn;
MLPPLinAlg alg;
MLPPReg regularization;
double cost_prev = 0;
int epoch = 1;
forwardPass();
while (true) {
cost_prev = Cost(y_hat, outputSet);
std::vector<double> error = alg.subtraction(y_hat, outputSet);
// Calculating the weight gradients
weights = alg.subtraction(weights, alg.scalarMultiply(learning_rate / n, alg.mat_vec_mult(alg.transpose(inputSet), alg.hadamard_product(error, avn.gaussianCDF(z, 1)))));
weights = regularization.regWeights(weights, lambda, alpha, reg);
// Calculating the bias gradients
bias -= learning_rate * alg.sum_elements(alg.hadamard_product(error, avn.gaussianCDF(z, 1))) / n;
forwardPass();
if (UI) {
MLPPUtilities::CostInfo(epoch, cost_prev, Cost(y_hat, outputSet));
MLPPUtilities::UI(weights, bias);
}
epoch++;
if (epoch > max_epoch) {
break;
}
}
}
void MLPPProbitReg::MLE(double learning_rate, int max_epoch, bool UI) {
MLPPActivation avn;
MLPPLinAlg alg;
MLPPReg regularization;
double cost_prev = 0;
int epoch = 1;
forwardPass();
while (true) {
cost_prev = Cost(y_hat, outputSet);
std::vector<double> error = alg.subtraction(outputSet, y_hat);
// Calculating the weight gradients
weights = alg.addition(weights, alg.scalarMultiply(learning_rate / n, alg.mat_vec_mult(alg.transpose(inputSet), alg.hadamard_product(error, avn.gaussianCDF(z, 1)))));
weights = regularization.regWeights(weights, lambda, alpha, reg);
// Calculating the bias gradients
bias += learning_rate * alg.sum_elements(alg.hadamard_product(error, avn.gaussianCDF(z, 1))) / n;
forwardPass();
if (UI) {
MLPPUtilities::CostInfo(epoch, cost_prev, Cost(y_hat, outputSet));
MLPPUtilities::UI(weights, bias);
}
epoch++;
if (epoch > max_epoch) {
break;
}
}
}
void MLPPProbitReg::SGD(double learning_rate, int max_epoch, bool UI) {
// NOTE: ∂y_hat/∂z is sparse
MLPPActivation avn;
MLPPLinAlg alg;
MLPPReg regularization;
double cost_prev = 0;
int epoch = 1;
while (true) {
std::random_device rd;
std::default_random_engine generator(rd());
std::uniform_int_distribution<int> distribution(0, int(n - 1));
int outputIndex = distribution(generator);
double y_hat = Evaluate(inputSet[outputIndex]);
double z = propagate(inputSet[outputIndex]);
cost_prev = Cost({ y_hat }, { outputSet[outputIndex] });
double error = y_hat - outputSet[outputIndex];
// Weight Updation
weights = alg.subtraction(weights, alg.scalarMultiply(learning_rate * error * ((1 / sqrt(2 * M_PI)) * exp(-z * z / 2)), inputSet[outputIndex]));
weights = regularization.regWeights(weights, lambda, alpha, reg);
// Bias updation
bias -= learning_rate * error * ((1 / sqrt(2 * M_PI)) * exp(-z * z / 2));
y_hat = Evaluate({ inputSet[outputIndex] });
if (UI) {
MLPPUtilities::CostInfo(epoch, cost_prev, Cost({ y_hat }, { outputSet[outputIndex] }));
MLPPUtilities::UI(weights, bias);
}
epoch++;
if (epoch > max_epoch) {
break;
}
}
forwardPass();
}
void MLPPProbitReg::MBGD(double learning_rate, int max_epoch, int mini_batch_size, bool UI) {
MLPPActivation avn;
MLPPLinAlg alg;
MLPPReg regularization;
double cost_prev = 0;
int epoch = 1;
// Creating the mini-batches
int n_mini_batch = n / mini_batch_size;
auto [inputMiniBatches, outputMiniBatches] = MLPPUtilities::createMiniBatches(inputSet, outputSet, n_mini_batch);
// Creating the mini-batches
for (int i = 0; i < n_mini_batch; i++) {
std::vector<std::vector<double>> currentInputSet;
std::vector<double> currentOutputSet;
for (int j = 0; j < n / n_mini_batch; j++) {
currentInputSet.push_back(inputSet[n / n_mini_batch * i + j]);
currentOutputSet.push_back(outputSet[n / n_mini_batch * i + j]);
}
inputMiniBatches.push_back(currentInputSet);
outputMiniBatches.push_back(currentOutputSet);
}
if (double(n) / double(n_mini_batch) - int(n / n_mini_batch) != 0) {
for (int i = 0; i < n - n / n_mini_batch * n_mini_batch; i++) {
inputMiniBatches[n_mini_batch - 1].push_back(inputSet[n / n_mini_batch * n_mini_batch + i]);
outputMiniBatches[n_mini_batch - 1].push_back(outputSet[n / n_mini_batch * n_mini_batch + i]);
}
}
while (true) {
for (int i = 0; i < n_mini_batch; i++) {
std::vector<double> y_hat = Evaluate(inputMiniBatches[i]);
std::vector<double> z = propagate(inputMiniBatches[i]);
cost_prev = Cost(y_hat, outputMiniBatches[i]);
std::vector<double> error = alg.subtraction(y_hat, outputMiniBatches[i]);
// Calculating the weight gradients
weights = alg.subtraction(weights, alg.scalarMultiply(learning_rate / outputMiniBatches.size(), alg.mat_vec_mult(alg.transpose(inputMiniBatches[i]), alg.hadamard_product(error, avn.gaussianCDF(z, 1)))));
weights = regularization.regWeights(weights, lambda, alpha, reg);
// Calculating the bias gradients
bias -= learning_rate * alg.sum_elements(alg.hadamard_product(error, avn.gaussianCDF(z, 1))) / outputMiniBatches.size();
y_hat = Evaluate(inputMiniBatches[i]);
if (UI) {
MLPPUtilities::CostInfo(epoch, cost_prev, Cost(y_hat, outputMiniBatches[i]));
MLPPUtilities::UI(weights, bias);
}
}
epoch++;
if (epoch > max_epoch) {
break;
}
}
forwardPass();
}
double MLPPProbitReg::score() {
MLPPUtilities util;
return util.performance(y_hat, outputSet);
}
void MLPPProbitReg::save(std::string fileName) {
MLPPUtilities util;
util.saveParameters(fileName, weights, bias);
}
double MLPPProbitReg::Cost(std::vector<double> y_hat, std::vector<double> y) {
MLPPReg regularization;
class MLPPCost cost;
return cost.MSE(y_hat, y) + regularization.regTerm(weights, lambda, alpha, reg);
}
std::vector<double> MLPPProbitReg::Evaluate(std::vector<std::vector<double>> X) {
MLPPLinAlg alg;
MLPPActivation avn;
return avn.gaussianCDF(alg.scalarAdd(bias, alg.mat_vec_mult(X, weights)));
}
std::vector<double> MLPPProbitReg::propagate(std::vector<std::vector<double>> X) {
MLPPLinAlg alg;
return alg.scalarAdd(bias, alg.mat_vec_mult(X, weights));
}
double MLPPProbitReg::Evaluate(std::vector<double> x) {
MLPPLinAlg alg;
MLPPActivation avn;
return avn.gaussianCDF(alg.dot(weights, x) + bias);
}
double MLPPProbitReg::propagate(std::vector<double> x) {
MLPPLinAlg alg;
return alg.dot(weights, x) + bias;
}
// gaussianCDF ( wTx + b )
void MLPPProbitReg::forwardPass() {
MLPPLinAlg alg;
MLPPActivation avn;
z = propagate(inputSet);
y_hat = avn.gaussianCDF(z);
}