c++ - Reading text file with floating point numbers faster and storing in vector of floats -

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i have c++ code written in visual studio 2010, reads text file ( contains tens of thousands of floating point numbers separated space).code reads text file contents , store vector of floating points.my problem , code taking alot of time read , copy vector.is there faster way this.some thing can done in visual studio c++ ( using boost libraries or mmap )

vector<float> replaybuffer; 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();     in.seekg(0,ios::beg);    while(!in.eof())    {    for(float f;in>>f;)        replaybuffer.push_back(f);    }    in.close(); }

if files big, consider memory mapped files : boost offer excellent library manipulate them cross platform (you mentioned mmap posix-unix command, , looks developing on windows)

also, consider reserving space in vector avoid dynamic reallocations replaybuffer.reserve(expected_final_size);

note:

  • do not use !in.eof() check if finished reading file, it bad practice.
  • if dont need filesizes, not compute it.

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