分段故障：11时打印动态数组 [英] Segmentation fault: 11 while printing dynamic arrays

问题描述

我有一个简单的C ++代码，其中我定义一个动态数组：

  std :: vector< double> IPWeights; 
  

然后将它传递给一个引用引用的函数

  void reference（std :: vector< double>& IPWeights）
  / pre> 
 
 
然后在我的主函数中，我改变了我的数组内容后，我想打印它：
  int size_weights = IPWeights.size（）; 
 
 for（int i = 0; i  {
 std :: cout } 
  
但在屏幕上我只看到分段错误11 > 
 
 
其中引用看起来像：
 向量< double>& IPWeights）
 {
 IPWeights [0] = 0.4500; 
 IPWeights [1] = 0.2648; 
 IPWeights [2] = 0.2648; 
 IPWeights [3] = 0.2648; 
 IPWeights [4] = 0.2519; 
 IPWeights [5] = 0.2519; 
 IPWeights [6] = 0.2519; 
} 
  
感谢任何建议，
提前感谢。 
解决方案
我的水晶球说你不为矢量分配内存。您应该执行以下操作之一：
 
 
 $ b 
 
 
 
初始化适当大小的向量：
  std :: vector< double> IPWeights（size_you_need）; 
  
 
 
 
 
调用 IPWeights.resize（）之前分配给它：
  std :: vector< double> IPWeights; 
 IPWeights.resize（size_you_need）; 
  
 
 
 
 
呼叫 IPWeights.push_back（）而不是通过索引分配：
  IPWeights.push_back（0.4500）; 
 IPWeights.push_back（0.2648）; 
 // ... 
  
 
 
 
 
I have a simple C++ code where I define a dynamic array as:
std::vector<double>IPWeights;
and then pass it to a function called reference with a reference (so I changed its content) like:
void reference (std::vector<double> &IPWeights)
and then in my main function, after I changed my arrays content I wanted to print it like:
int size_weights=IPWeights.size();

for (int i=0; i<size_weights; i++)
{
    std::cout<<IPWeights[i]<<std::endl;
}
but in the screen I only see "segmentation fault 11".

where the reference is simply looks like:
void reference( std::vector<double> &IPWeights)
{
    IPWeights[0]=0.4500;
    IPWeights[1]=0.2648;
    IPWeights[2]=0.2648;
    IPWeights[3]=0.2648;
    IPWeights[4]=0.2519;
    IPWeights[5]=0.2519;
    IPWeights[6]=0.2519;
}
Any advice is appreciated,
Thanks in advance. 
解决方案
My crystal ball says that you don't allocate memory for the vector. You should do one of the following:


Initialize vector with appropriate size:
std::vector<double> IPWeights(size_you_need);

Call IPWeights.resize() before assigning to it:
std::vector<double> IPWeights;
IPWeights.resize(size_you_need);

Call IPWeights.push_back() instead of assigning by index:
IPWeights.push_back(0.4500);
IPWeights.push_back(0.2648);
//...



                        
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