matrix.c

#include "matrix.h"
#include <stdlib.h>

static unsigned int seed = 2121;

static unsigned int gen_rand() {
  seed ^= seed >> 16;
  seed *= 17;
  seed ^= seed << 15;
  seed += 15;
  return seed;
}

int matrix_alloc(int row, int col, float **mat) {
  if (row <= 0 || col <= 0 || mat == NULL)
    return 1;
  *mat = malloc(row * col * sizeof(float));
  if (*mat == NULL)
    return 2;
  return 0;
}

int matrix_rand(float *mat, int row, int col) {
  if (row <= 0 || col <= 0 || mat == NULL)
    return 1;

  for (int i = 0; i < row; i++) {
    for (int j = 0; j < col; j++) {
      unsigned int r = gen_rand();
      float val = ((float)r / (float)0xFFFFFFFF) * 2.0f - 1.0f;
      mat[i * col + j] = val;
    }
  }
  return 0;
}

void matrix_free(float **mat) {
  if (mat != NULL && *mat != NULL) {
    free(*mat);
    *mat = NULL;
  }
}

int transpose(const float *mat, int row, int col, float **out_mat) {
  if (row <= 0 || col <= 0 || mat == NULL || out_mat == NULL)
    return 1;

  float *new_mat = NULL;
  if (matrix_alloc(col, row, &new_mat) != 0) {
    return 2;
  }

  for (int i = 0; i < row; i++) {
    for (int j = 0; j < col; j++) {
      new_mat[j * row + i] = mat[i * col + j];
    }
  }

  *out_mat = new_mat;
  return 0;
}

int matrix_mult(const float *mat_a, int row_a, int col_a, const float *mat_b,
                int row_b, int col_b, float **out_mat) {
  if (row_a <= 0 || row_b <= 0 || col_a <= 0 || col_b <= 0 || mat_a == NULL ||
      mat_b == NULL || out_mat == NULL || col_a != row_b)
    return 1;

  float *mat = NULL;
  if (matrix_alloc(row_a, col_b, &mat) != 0) {
    return 2;
  }

  for (int i = 0; i < row_a; i++) {
    for (int j = 0; j < col_b; j++) {
      mat[i * col_b + j] = 0.0f;
      for (int k = 0; k < col_a; k++) {
        mat[i * col_b + j] += mat_a[i * col_a + k] * mat_b[k * col_b + j];
      }
    }
  }

  *out_mat = mat;
  return 0;
}

int matrix_add(const float *mat_a, const float *mat_b, int row, int col,
               float **out_mat) {
  if (row <= 0 || col <= 0 || mat_a == NULL || mat_b == NULL ||
      out_mat == NULL) {
    return 1;
  }

  float *mat = NULL;
  if (matrix_alloc(row, col, &mat) != 0) {
    return 2;
  }

  int total = row * col;
  for (int i = 0; i < total; i++) {
    mat[i] = mat_a[i] + mat_b[i];
  }

  *out_mat = mat;
  return 0;
}

int matrix_sub(const float *mat_a, const float *mat_b, int row, int col,
               float **out_mat) {
  if (row <= 0 || col <= 0 || mat_a == NULL || mat_b == NULL ||
      out_mat == NULL) {
    return 1;
  }

  float *mat = NULL;
  if (matrix_alloc(row, col, &mat) != 0) {
    return 2;
  }

  int total = row * col;
  for (int i = 0; i < total; i++) {
    mat[i] = mat_a[i] - mat_b[i];
  }

  *out_mat = mat;
  return 0;
}

int matrix_map(const float *mat, int row, int col, float (*func)(float),
               float **out_mat) {
  if (row <= 0 || col <= 0 || mat == NULL || func == NULL || out_mat == NULL)
    return 1;

  float *new_mat = NULL;
  if (matrix_alloc(row, col, &new_mat) != 0) {
    return 2;
  }

  int total_elements = row * col;
  for (int i = 0; i < total_elements; i++) {
    new_mat[i] = func(mat[i]);
  }

  *out_mat = new_mat;
  return 0;
}

int matrix_hadamard(const float *mat_a, const float *mat_b, int row, int col,
                    float **out_mat) {
  if (row <= 0 || col <= 0 || mat_a == NULL || mat_b == NULL || out_mat == NULL)
    return 1;

  float *mat = NULL;
  if (matrix_alloc(row, col, &mat) != 0)
    return 2;

  int total = row * col;
  for (int i = 0; i < total; i++) {
    mat[i] = mat_a[i] * mat_b[i];
  }

  *out_mat = mat;
  return 0;
}

int matrix_scale(float *mat, int row, int col, float scalar) {
  if (row <= 0 || col <= 0 || mat == NULL)
    return 1;

  int total = row * col;
  for (int i = 0; i < total; i++) {
    mat[i] *= scalar;
  }

  return 0;
}