add: json file function implemented

1 files changed, 80 insertions, 0 deletions

diff --git a/src/main.c b/src/main.c
new file mode 100644
index 0000000..8c82260
--- /dev/null
+++ b/src/main.c
@@ -0,0 +1,80 @@
+#include <stdio.h>
+#include <stdint.h>
+#include <string.h>
+#include <json-c/json.h>
+
+#include "neural.h"
+
+typedef struct Array {
+    double *data;
+    size_t shape[2];
+} Array;
+
+static Array json_read(const char *filepath);
+
+Array json_read(const char *filepath)
+{
+    Array out;
+    FILE *fp;
+    char *fp_buffer;
+    size_t ret;
+    int64_t fp_size;
+
+    fp = fopen(filepath, "r");
+    if (fp == NULL) goto json_read_error;
+
+    ret = (size_t)fseek(fp, 0L, SEEK_END);
+    if ((int)ret == -1) goto json_read_error;
+
+    fp_size = ftell(fp);
+    if (fp_size == -1) goto json_read_error;
+    rewind(fp);
+
+    fp_buffer = calloc(sizeof(char), fp_size);
+    if (fp_buffer == NULL) goto json_read_error;
+
+    ret = fread(fp_buffer, sizeof(char), (size_t)fp_size, fp);
+    if (ret != (size_t)fp_size) {
+        fprintf(stderr, "json_read() Error: fread bytes '%zd' does not match with buffer size '%zd'", ret, (size_t)fp_size);
+        exit(1);
+    }
+
+
+    json_object *json_obj;
+    json_obj = json_tokener_parse(fp_buffer);
+    size_t json_obj_length = json_object_array_length(json_obj);
+
+    out.shape[0] = (size_t)json_obj_length;
+    out.shape[1] = 4;
+    out.data = calloc(out.shape[0] * out.shape[1], sizeof(out.data[0]));
+
+    for (int i = 0; i < json_object_array_length(json_obj); i++) {
+        json_object *item = json_object_array_get_idx(json_obj, i);
+        out.data[4*i] = json_object_get_double(json_object_object_get(item, "area"));
+        out.data[4*i + 1] = json_object_get_double(json_object_object_get(item, "longitude"));
+        out.data[4*i + 2] = json_object_get_double(json_object_object_get(item, "latitude"));
+        out.data[4*i + 3] = json_object_get_double(json_object_object_get(item, "price"));
+    }
+
+    json_object_put(json_obj);
+    fclose(fp);
+    return out;
+
+json_read_error:
+    perror("json_read() Error");
+    exit(1);
+}
+
+int main(void) {
+    Array json_data = json_read("data/housing_rent.json");
+    printf("area\tlong\tlat\tprice\n");
+    for (int i = 0; i < json_data.shape[0]; i++) {
+        printf("%3.1lf\t%3.2lf\t%3.2lf\t%lf\n",
+                json_data.data[4*i],
+                json_data.data[4*i + 1],
+                json_data.data[4*i + 2],
+                json_data.data[4*i + 3]);
+    }
+    free(json_data.data);
+    return 0;
+}