初始化结构的数组，为什么使用结构变量无法正常工作 [英] Initializing an array of structs, why does using struct variables not work

问题描述

我非常新C ..将AP preciate，如果有人可以帮助理解为什么在管路13,14和16 code没有工作，但17-20行的作品。

通过第一个选项（线13，14和16）我得到的错误

 错误：初始元素不是常数
 

这是什么意思？此外，这是否意味着人们不能使用某些类型的变量产生新的变数？

感谢您。

  //定义结构有一个良好的
  5结构良好{
  6字符goodname;
  7双磷; //比例开始
  8 INT THETA; //平均效用
  9 INT西格玛; //错误的方差
 10};
 11
 12 //货物H和L
 13结构良好H = {.goodname ='H'，P = 0.5，西塔= 100，西格玛= 20};
 14结构良好L = {.goodname =L，P = 0.5，西塔= 75，西格玛= 20};
 15
 16结构好货[2] = {H，L}; // **不工作** // ** **工程
 17结构好货[2] = {
 18 {.goodname =H，P = 0.5，西塔= 100，西格玛= 20}，
 19 {.goodname =L，P = 0.5，西塔= 75，西格玛= 20}
 20};
 

解决方案

H和L是包含数据的存储位置。声明：

 结构体好货[2] = {H，L}; // **不工作**
 

意味着产品应指向H和L，或包含相同的值H和L

无论，复制从H到产品中的数据和L [0]和[1]或修改产品是一个指针数组，作为

 结构体好货* [2]; 产品[0] =＆放大器; H：
 产品[1] =＆放大器; L，
 

I am extremely new to C. Would appreciate if someone can help understand why code in lines 13,14 and 16 does not work, but lines 17-20 works.

With the first option (lines 13, 14 and 16) I get the error

error: initializer element is not constant

What does this mean? Also, does this mean one cannot use variables of certain type to generate new variables?

Thank you.

// Define structure for a good
  5 struct good {
  6     char goodname;
  7     double p; //starting proportion
  8     int theta; //average utility
  9     int sigma; //variance of error
 10 };
 11
 12 // The goods H and L
 13 struct good H = {.goodname = 'H', .p = 0.5, .theta = 100, .sigma = 20};
 14 struct good L = {.goodname = 'L', .p = 0.5, .theta = 75, .sigma = 20};
 15
 16 struct good goods[2] = {H, L}; // **Does not work**

 // ** Works**
 17 struct good goods[2] = {
 18     {.goodname = 'H', .p = 0.5, .theta = 100, .sigma = 20},
 19     {.goodname = 'L', .p = 0.5, .theta = 75, .sigma = 20}
 20 };

解决方案

H and L are storage locations that contain data. The statement:

 struct good goods[2] = {H, L}; // **Does not work**

implies that goods should point to H and L, or contain the same values as H and L.

Either, copy the data from H and L to goods[0] and [1] or modify goods to be an array of pointers, as:

 struct good *goods[2];

 goods[0] = &H;
 goods[1] = &L;

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