c - 从 C 中的另一个文件读取输入的家庭作业程序

Question

For this lab, you are to write a a program that will first read in the heights and weights of a series of people from a file named values.dat. Create this file using your editor so that each line contains a height and corresponding weight. For instance, it might look likea:

60.0  125.0
48.0  100.0

等等。

接下来创建一个名为 stats.h 的文件，其中包含以下内容:

#define MAXNUM 100
typedef struct person
{
  double height;
  double weight;
} Person;

//prototypes follow:
numPeople = getData(File *input, Person[] people, int MAXNUM);
getAverages(Person[] people, double *aveHeight, double *aveWeight, int numPeople)
getStandardDevs(Person[] people, double aveHeight, double aveWeight, 
                      double *stdHeight, double *stdWeight, int numPeople);

主程序将如下所示:

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

void main(void)
{
  char filename[] = "values.dat";
  FILE *input;
  Person people[MAXNUM];
  int numPeople;
  double aveHeight, aveWeight, stdHeight, stdWeight;

  numPeople = getData(input, people, MAXNUM)
  fclose(input);
  getAverages(people, &aveHeight, &aveWeight, numPeople)
  getStandardDevs(people, aveHeight, aveWeight, &stdHeight, &stdWeight, numPeople)

  printf("The average height is %lf\n", aveHeight);
  printf("The average weight is %lf\n", aveWeight);
  printf("The standard deviation of the heights is %lf\n", stdHeight);
  printf("The standard deviation of the weights is %lf\n", stdWeight);
}

现在，编写函数 getData , getAverages ，和getStandardDevs 。将它们放在主程序之后。

一系列数字 x[1], x[2] ... x[n] 的标准差公式为

std = sqrt( sum( (x[i] - xbar)**2 ) / (n-1) )

其中xbar是x的平均值，n是样本数，和 **2 均方。

请记住，要使用 sqrt，您必须 #include <math.h>并且将 -lm 添加到编译行。

上面的文本是实验室，当我尝试创建 3 个文件(values.dat、stats.h 和主程序)时，在尝试使用 -gcc -o 进行编译时，我立即收到错误lab6 lab6.c -lm

我现在的主程序代码是

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include "stats.h"

void main(void)
{
  char filename[] = "values.dat";
  FILE *input;
  Person people[MAXNUM];
  int numPeople;
  double aveHeight, aveWeight, stdHeight, stdWeight;

  numPeople = getData(input, people, MAXNUM)
  fclose(input);
  getAverages(people, &aveHeight, &aveWeight, numPeople)
  getStandardDevs(people, aveHeight, aveWeight, &stdHeight, &stdWeight, numPeople)

  printf("The average height is %lf\n", aveHeight);
  printf("The average weight is %lf\n", aveWeight);
  printf("The standard deviation of the heights is %lf\n", stdHeight);
  printf("The standard deviation of the weights is %lf\n", stdWeight);
}

int getData(File *input, Person[] people, int MAXNUM)
{

}

double getAverages(Person[] people, double *aveHeight, double *aveWeight, int numPeople)
{

}

double getStandardDevs(Person[] people, double aveHeight, double aveWeight, double *stdHeight, double *stdWeight, int numPeople)
{


}

我添加了函数并尝试编译。

我在行尾使用 -lm 编译的行是否正确。
如果有人可以帮助我使用这三个文件进行编译，那就太棒了，或者如果有人可以帮助解决任何代码。

我遇到的错误

In file included from lab6.c:4:0:
stats.h:9:9: error: unknown type name ‘File’
 getData(File *input, Person[] people, int MAXNUM);
         ^
stats.h:9:31: error: expected ‘;’, ‘,’ or ‘)’ before ‘people’
 getData(File *input, Person[] people, int MAXNUM);
                               ^
stats.h:10:22: error: expected ‘;’, ‘,’ or ‘)’ before ‘people’
 getAverages(Person[] people, double *aveHeight, double *aveWeight, int numPeopl
                      ^
stats.h:11:26: error: expected ‘;’, ‘,’ or ‘)’ before ‘people’
 getStandardDevs(Person[] people, double aveHeight, double aveWeight,
                          ^
lab6.c: In function ‘main’:
lab6.c:14:15: warning: implicit declaration of function ‘getData’ [-Wimplicit-function-declaration]
   numPeople = getData(input, people, MAXNUM);
               ^
lab6.c:16:3: warning: implicit declaration of function ‘getAverages’ [-Wimplicit-function-declaration]
   getAverages(people, &aveHeight, &aveWeight, numPeople);
   ^
lab6.c:17:3: warning: implicit declaration of function ‘getStandardDevs’ [-Wimplicit-function-declaration]
   getStandardDevs(people, aveHeight, aveWeight, &stdHeight, &stdWeight, numPeop
   ^
lab6.c: At top level:
lab6.c:25:13: error: unknown type name ‘File’
 int getData(File *input, Person[] people, int MAXNUM)
             ^
lab6.c:25:35: error: expected ‘;’, ‘,’ or ‘)’ before ‘people’
 int getData(File *input, Person[] people, int MAXNUM)
                                   ^
lab6.c:30:29: error: expected ‘;’, ‘,’ or ‘)’ before ‘people’
 double getAverages(Person[] people, double *aveHeight, double *aveWeight, int n
                             ^
lab6.c:35:33: error: expected ‘;’, ‘,’ or ‘)’ before ‘people’
 double getStandardDevs(Person[] people, double aveHeight, double aveWeight, dou
                                 ^

谢谢

Answer 1

File与 FILE 不同。 <stdio.h>定义FILE这就是你应该使用的。

我不知道修复此错误(将您的 File 引用更改为 FILE )是否能让您进行编译，因为可能还有其他错误被此错误隐藏。然而，这将是编译代码时需要修复的第一个错误。