读取iris数据集中的花萼长度数据

可以使用以下代码读取iris数据集中的花萼长度数据：

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#define MAX_LINE_LENGTH 1024
#define NUM_FEATURES 4
#define NUM_SAMPLES 150

int main() {
    FILE *fp;
    char line[MAX_LINE_LENGTH];
    float sepal_length[NUM_SAMPLES];

    fp = fopen("iris.data", "r");
    if (fp == NULL) {
        printf("Failed to open file\n");
        exit(1);
    }

    int i = 0;
    while (fgets(line, MAX_LINE_LENGTH, fp) != NULL) {
        char *token = strtok(line, ",");
        for (int j = 0; j < NUM_FEATURES; j++) {
            if (j == 0) {
                sepal_length[i] = atof(token);
            }
            token = strtok(NULL, ",");
        }
        i++;
    }

    fclose(fp);

    // Print out the sepal length data
    for (int i = 0; i < NUM_SAMPLES; i++) {
        printf("%f\n", sepal_length[i]);
    }

    return 0;
}