feat: add VecData structure

inc/utils.h

@@ -1,5 +1,8 @@
 
-typedef char* VecData;
+typedef struct {
+    int id;
+    float* vector;
+} VecData;
 
 float vec_dist(VecData x, VecData y);
-void fvecs_read(const char* filename, int* bound, float** vectors, int* num_vectors, int* vector_dimension);
+VecData* fvecs_read(const char* filename, int* bounds);

src/test.c

@@ -1,27 +1,16 @@
 #include <stdio.h>
 #include <stdlib.h>
-#include "hnsw.h"
 #include "utils.h"
 
 
 int main() {
-    const char* filename = "../dataset/siftsmall_base.fvecs";
-    int bound[2] = {2, 5};
-    float* vectors;
-    int num_vectors, vector_dimension;
-    fvecs_read(filename, bound, &vectors, &num_vectors, &vector_dimension);
 
-    printf("Number of vectors: %d\n", num_vectors);
-    printf("Vector dimension: %d\n", vector_dimension);
-    int i, j;
-    for (i = 0; i < num_vectors; i++) {
-        printf("Vector %d: ", i);
-        for (j = 0; j < vector_dimension; j++) {
-            printf("%f ", vectors[i * vector_dimension + j]);
-        }
-        printf("\n");
+    VecData* vecs = fvecs_read("../dataset/siftsmall_base.fvecs", NULL);
+    for (int i = 0; i < 10000; i++) {
+        printf("%f\n", vecs[i].vector[0]);
     }
+    free(vecs);
 
-    free(vectors);
     return 0;
+
 }

src/utils.c

@@ -6,87 +6,65 @@
 #include <assert.h>
 
 float vec_dist(VecData x, VecData y) {
-    float dist = 0.0f;
-    while (*x != '\0' && *y != '\0') {
-        int xi = *x - '0';
-        int yi = *y - '0';
-        dist += pow(xi - yi, 2);
-        x++;
-        y++;
+    float sum = 0.0;
+    for (int i = 0; i < 128; i++) {
+        float diff = x.vector[i] - y.vector[i];
+        sum += diff * diff;
     }
-    return sqrt(dist);
+    return sqrt(sum);
 }
 
-void fvecs_read(const char* filename, int* bound, float** vectors, int* num_vectors, int* vector_dimension) {
+VecData* fvecs_read(const char* filename, int* bounds) {
     FILE* fid = fopen(filename, "rb");
     if (fid == NULL) {
-        fprintf(stderr, "I/O error: Unable to open the file %s\n", filename);
+        fprintf(stderr, "I/O error : Unable to open the file %s\n", filename);
         exit(EXIT_FAILURE);
     }
 
-    // Read the vector size
-    int d;
+    int d; 
     fread(&d, sizeof(int), 1, fid);
 
-    // Get the file size
+
     fseek(fid, 0, SEEK_END);
     long file_size = ftell(fid);
     fseek(fid, 0, SEEK_SET);
-
-    // Get the number of vectors
     long vec_size = (long) d * sizeof(float);
     long vec_count = (file_size - sizeof(int)) / vec_size;
 
-    // Apply the bounds if specified
     int a = 1;
-    int b = vec_count;
-    if (bound != NULL) {
-        if (bound[1] == 1) {
-            b = bound[0];
-        } else if (bound[1] == 2) {
-            a = bound[0];
-            b = bound[1];
+    int bmax = vec_count;
+    int b = bmax;
+
+    if (bounds != NULL) {
+        if (bounds[1] == 1) {
+            b = bounds[0];
+        } else if (bounds[1] == 2) {
+            a = bounds[0];
+            b = bounds[1];
         }
     }
 
-    // Check if the bounds are valid
-    if (a < 1 || b < a || b > vec_count) {
-        *vectors = NULL;
+    if (a < 1 || b > bmax || b < a) {
+        VecData* v = NULL;
         fclose(fid);
-        return;
+        return v;
     }
 
-    // Compute the number of vectors to read
     int n = b - a + 1;
+    fseek(fid, (a - 1) * vec_size, SEEK_SET);
 
-    // Read the vectors
-    *vectors = malloc(n * d * sizeof(float));
-    float* ptr = *vectors;
-    for (int i = 0; i < vec_count; i++) {
-        // Read the vector size
-        int vec_d;
-        fread(&vec_d, sizeof(int), 1, fid);
-
-        // Check if the vector size is correct
-        if (vec_d != d) {
-            fprintf(stderr, "Error: Vector %d has incorrect dimension %d (expected %d)\n", i + 1, vec_d, d);
-            fclose(fid);
-            free(*vectors);
-            *vectors = NULL;
-            return;
-        }
-
-        // Read the vector data
-        fread(ptr, sizeof(float), d, fid);
-        ptr += d;
-
-        // Stop reading if we have read enough vectors
-        if (i >= b - 1) {
-            break;
-        }
+    
+    // Read n vectors
+    VecData* v = malloc(n * sizeof(VecData));
+    for (int i = 0; i < n; i++) {
+        VecData vec;
+        vec.id = i + a;
+        vec.vector = malloc(d * sizeof(float));
+        fread(vec.vector, sizeof(float), d, fid);
+        v[i] = vec;
     }
 
-    *vector_dimension = d;
-    *num_vectors = n;
+
     fclose(fid);
+    return v;
 }