Question

我有一个浮点数的向量，我试图找出向量中每个包含72个浮点数的段的总数。我用从文本文件中读取的浮点数填充向量.I我试图从文本文件和向量的大小找到它，它们是否相同？。他们会给出正确的答案。以下是我使用的方式这种方式给我一个大于实际值的值，有人可以帮忙吗？

long fileSizeVector;
long fileSize;
long fileSizes;
vector<float> ReplayBufferVector;
ifstream in;
in.open("fileName.txt");
if(in.is_open())
{
    in.setf(ios::fixed);
    in.precision(3);
    in.seekg(0,ios::end);
   fileSizes = in.tellg();
   fileSize = fileSizes/((72)*sizeof(float));
   in.seekg(0,ios::beg);

   while(!in.eof())
   {
   for(float f;in>>f;)
       ReplayBufferVector.push_back(f);
   }
   fileSizeVector = ReplayBufferVector.size()/72*sizeof(float);
in.close();
}

Answer 1

最简单的方法是计算花车的数量保留正确的向量大小然后将所有浮点数读入向量..

std::ifstream   file("fileName.txt";
std::size_t     size = std::distance(std::istream_iterator<float>(file),
                                     std::istream_iterator<float>());

file.close();
file.open("fileName.txt");
std::vector<float>  data(size);   // allocate enough space
                                  // to hold all the floats you need.
                                  // Normally I would use the iterators to 
                                  // construct the vector but because it is
                                  // so large I want to reserve the space
                                  // for it first.

// copy from the file to the vector.
std::copy(std::istream_iterator<float>(file),
          std::istream_iterator<float>()
          data.begin());

或者，如果您只想阅读文件：

std::ifstream      file("fileName.txt");
std::vector<float> data(std::istream_iterator<float>(file), 
                        std::istream_iterator<float>());

查找从文本文件中读取的浮点数向量的大小

1 个答案: