c - 将 .dat 文件中的 double float 存储到一维数组中

Question

所以我在从 .dat 文件中存储一些数字时遇到了一些困难。文件如下:

1
2
7
10
9
4
0
5
6
8
3

我必须尝试检索此信息的代码是:

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

#define N 11

int main(int argc, char** argv) {

    //Declare variables: number of elements, counter, array, & valuesto
    //print
    int i;
    double a[N], num, temp;
    FILE* dat;

    //Print space for program cleanliness
    printf("\n");

    //Open file
    dat = fopen("zero.dat", "r");      

    //Initialize i  
    i=0;

    //Read in infromation from file
    while(!feof(dat) && i < N){
        printf("This is loop number %d\n", i);
        num = fscanf(dat,"%lf", &temp);
        printf("Temp variable is stored as: %f\n", temp);
        printf("Number of characters read in: %d\n\n", num);
        a[i] = temp;
        i++;
    }        

    fclose(dat);    

    for(int j=0;j<i;j++){

        printf("%f\n", a[j]);

    }

    //Exit program
    exit(EXIT_SUCCESS);
}
/**************************************************************************/

输出是:

This is loop number 0
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 1
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 2
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 3
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 4
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 5
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 6
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 7
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 8
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 9
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

This is loop number 10
Temp variable is stored as: 0.000000
Number of characters read in: 1541763072

0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000
0.000000

此外，需要注意的是，我使用的是 NetBeans IDE 8.0.2； zero.dat 文件位于与源相同的项目文件夹中。

Answer 1

您的代码打印 Number of characters read in: 1541763072 因为 fscanf 返回一个 int 并且您将其收集在一个 double 变量中，不确定为什么放置垃圾值但是把它改成像这样的 int 变量

int j;
j=fscanf(dat,"%lf", &temp);
printf("Number of characters read in: %d\n\n", j);

检查文件是否存在是一个很好的编程习惯。如果文件不存在，你只会得到一个段错误，你不会知道为什么它会返回一个段错误。而是处理它

dat = fopen("zero.dat", "r");
if(dat == NULL)
{
     //your message
     return;
}