pmlpp/mlpp/dual_svc/dual_svc_old.cpp
2023-04-22 17:17:58 +02:00

245 lines
7.0 KiB
C++

//
// DualSVC.cpp
//
// Created by Marc Melikyan on 10/2/20.
//
#include "dual_svc_old.h"
#include "../activation/activation_old.h"
#include "../cost/cost_old.h"
#include "../lin_alg/lin_alg_old.h"
#include "../regularization/reg_old.h"
#include "../utilities/utilities.h"
#include <iostream>
#include <random>
MLPPDualSVCOld::MLPPDualSVCOld(std::vector<std::vector<real_t>> p_inputSet, std::vector<real_t> p_outputSet, real_t p_C, std::string p_kernel) {
inputSet = p_inputSet;
outputSet = p_outputSet;
n = p_inputSet.size();
k = p_inputSet[0].size();
C = p_C;
kernel = p_kernel;
y_hat.resize(n);
bias = MLPPUtilities::biasInitialization();
alpha = MLPPUtilities::weightInitialization(n); // One alpha for all training examples, as per the lagrangian multipliers.
K = kernelFunction(inputSet, inputSet, kernel); // For now this is unused. When non-linear kernels are added, the K will be manipulated.
}
std::vector<real_t> MLPPDualSVCOld::modelSetTest(std::vector<std::vector<real_t>> X) {
return Evaluate(X);
}
real_t MLPPDualSVCOld::modelTest(std::vector<real_t> x) {
return Evaluate(x);
}
void MLPPDualSVCOld::gradientDescent(real_t learning_rate, int max_epoch, bool UI) {
class MLPPCostOld cost;
MLPPLinAlgOld alg;
real_t cost_prev = 0;
int epoch = 1;
forwardPass();
while (true) {
cost_prev = Cost(alpha, inputSet, outputSet);
alpha = alg.subtraction(alpha, alg.scalarMultiply(learning_rate, cost.dualFormSVMDeriv(alpha, inputSet, outputSet)));
alphaProjection();
// Calculating the bias
real_t biasGradient = 0;
for (uint32_t i = 0; i < alpha.size(); i++) {
real_t sum = 0;
if (alpha[i] < C && alpha[i] > 0) {
for (uint32_t j = 0; j < alpha.size(); j++) {
if (alpha[j] > 0) {
sum += alpha[j] * outputSet[j] * alg.dot(inputSet[j], inputSet[i]); // TO DO: DON'T forget to add non-linear kernelizations.
}
}
}
biasGradient = (1 - outputSet[i] * sum) / outputSet[i];
break;
}
bias -= biasGradient * learning_rate;
forwardPass();
// UI PORTION
if (UI) {
MLPPUtilities::CostInfo(epoch, cost_prev, Cost(alpha, inputSet, outputSet));
MLPPUtilities::UI(alpha, bias);
std::cout << score() << std::endl; // TO DO: DELETE THIS.
}
epoch++;
if (epoch > max_epoch) {
break;
}
}
}
// void MLPPDualSVCOld::SGD(real_t learning_rate, int max_epoch, bool UI){
// class MLPPCostOld cost;
// MLPPActivationOld avn;
// MLPPLinAlgOld alg;
// MLPPRegOld regularization;
// real_t 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);
// cost_prev = Cost(alpha, inputSet[outputIndex], outputSet[outputIndex]);
// // Bias updation
// bias -= learning_rate * costDeriv;
// y_hat = Evaluate({inputSet[outputIndex]});
// if(UI) {
// MLPPUtilities::CostInfo(epoch, cost_prev, Cost(alpha));
// MLPPUtilities::UI(weights, bias);
// }
// epoch++;
// if(epoch > max_epoch) { break; }
// }
// forwardPass();
// }
// void MLPPDualSVCOld::MBGD(real_t learning_rate, int max_epoch, int mini_batch_size, bool UI){
// class MLPPCostOld cost;
// MLPPActivationOld avn;
// MLPPLinAlgOld alg;
// MLPPRegOld regularization;
// real_t 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);
// while(true){
// for(int i = 0; i < n_mini_batch; i++){
// std::vector<real_t> y_hat = Evaluate(inputMiniBatches[i]);
// std::vector<real_t> z = propagate(inputMiniBatches[i]);
// cost_prev = Cost(z, outputMiniBatches[i], weights, C);
// // Calculating the weight gradients
// weights = alg.subtraction(weights, alg.scalarMultiply(learning_rate/n, alg.mat_vec_mult(alg.transpose(inputMiniBatches[i]), cost.HingeLossDeriv(z, outputMiniBatches[i], C))));
// weights = regularization.regWeights(weights, learning_rate/n, 0, "Ridge");
// // Calculating the bias gradients
// bias -= learning_rate * alg.sum_elements(cost.HingeLossDeriv(y_hat, outputMiniBatches[i], C)) / n;
// forwardPass();
// y_hat = Evaluate(inputMiniBatches[i]);
// if(UI) {
// MLPPUtilities::CostInfo(epoch, cost_prev, Cost(z, outputMiniBatches[i], weights, C));
// MLPPUtilities::UI(weights, bias);
// }
// }
// epoch++;
// if(epoch > max_epoch) { break; }
// }
// forwardPass();
// }
real_t MLPPDualSVCOld::score() {
MLPPUtilities util;
return util.performance(y_hat, outputSet);
}
void MLPPDualSVCOld::save(std::string fileName) {
MLPPUtilities util;
util.saveParameters(fileName, alpha, bias);
}
real_t MLPPDualSVCOld::Cost(std::vector<real_t> alpha, std::vector<std::vector<real_t>> X, std::vector<real_t> y) {
class MLPPCostOld cost;
return cost.dualFormSVM(alpha, X, y);
}
std::vector<real_t> MLPPDualSVCOld::Evaluate(std::vector<std::vector<real_t>> X) {
MLPPActivationOld avn;
return avn.sign(propagate(X));
}
std::vector<real_t> MLPPDualSVCOld::propagate(std::vector<std::vector<real_t>> X) {
MLPPLinAlgOld alg;
std::vector<real_t> z;
for (uint32_t i = 0; i < X.size(); i++) {
real_t sum = 0;
for (uint32_t j = 0; j < alpha.size(); j++) {
if (alpha[j] != 0) {
sum += alpha[j] * outputSet[j] * alg.dot(inputSet[j], X[i]); // TO DO: DON'T forget to add non-linear kernelizations.
}
}
sum += bias;
z.push_back(sum);
}
return z;
}
real_t MLPPDualSVCOld::Evaluate(std::vector<real_t> x) {
MLPPActivationOld avn;
return avn.sign(propagate(x));
}
real_t MLPPDualSVCOld::propagate(std::vector<real_t> x) {
MLPPLinAlgOld alg;
real_t z = 0;
for (uint32_t j = 0; j < alpha.size(); j++) {
if (alpha[j] != 0) {
z += alpha[j] * outputSet[j] * alg.dot(inputSet[j], x); // TO DO: DON'T forget to add non-linear kernelizations.
}
}
z += bias;
return z;
}
void MLPPDualSVCOld::forwardPass() {
MLPPActivationOld avn;
z = propagate(inputSet);
y_hat = avn.sign(z);
}
void MLPPDualSVCOld::alphaProjection() {
for (uint32_t i = 0; i < alpha.size(); i++) {
if (alpha[i] > C) {
alpha[i] = C;
} else if (alpha[i] < 0) {
alpha[i] = 0;
}
}
}
real_t MLPPDualSVCOld::kernelFunction(std::vector<real_t> u, std::vector<real_t> v, std::string kernel) {
MLPPLinAlgOld alg;
if (kernel == "Linear") {
return alg.dot(u, v);
}
return 0;
}
std::vector<std::vector<real_t>> MLPPDualSVCOld::kernelFunction(std::vector<std::vector<real_t>> A, std::vector<std::vector<real_t>> B, std::string kernel) {
MLPPLinAlgOld alg;
if (kernel == "Linear") {
return alg.matmult(inputSet, alg.transpose(inputSet));
}
return std::vector<std::vector<real_t>>();
}