Files
libpostal/src/logistic_regression_trainer.h

50 lines
2.1 KiB
C

#ifndef LOGISTIC_REGRESSION_TRAINER_H
#define LOGISTIC_REGRESSION_TRAINER_H
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include "averaged_perceptron_tagger.h"
#include "collections.h"
#include "features.h"
#include "logistic_regression.h"
#include "minibatch.h"
#include "sparse_matrix.h"
#include "string_utils.h"
#include "stochastic_gradient_descent.h"
#include "tokens.h"
#include "trie.h"
/**
* Helper struct for training logistic regression model
*/
typedef struct logistic_regression_trainer {
trie_t *feature_ids; // Trie mapping features to array indices
size_t num_features; // Number of features
khash_t(str_uint32) *label_ids; // Hashtable mapping labels to array indices
size_t num_labels; // Number of labels
double_matrix_t *weights; // Matrix of logistic regression weights
double_matrix_t *gradient; // Gradient matrix to be reused
khash_t(int_set) *unique_columns; // Unique columns set
uint32_array *batch_columns; // Unique columns as array
uint32_array *last_updated; // Array of length N indicating the last time each feature was updated
double lambda; // Regularization weight
uint32_t iters; // Number of iterations, used to decay learning rate
uint32_t epochs; // Number of epochs
double gamma_0; // Initial learning rate
} logistic_regression_trainer_t;
logistic_regression_trainer_t *logistic_regression_trainer_init(trie_t *feature_ids, khash_t(str_uint32) *label_ids, double gamma_0, double lambda);
bool logistic_regression_trainer_train_batch(logistic_regression_trainer_t *self, feature_count_array *features, cstring_array *labels);
double logistic_regression_trainer_batch_cost(logistic_regression_trainer_t *self, feature_count_array *features, cstring_array *labels);
bool logistic_regression_trainer_finalize(logistic_regression_trainer_t *self);
void logistic_regression_trainer_destroy(logistic_regression_trainer_t *self);
#endif