c++ 에서 float point precision 설정

http://www.cplusplus.com/reference/iostream/manipulators/fixed/

// modify basefield
#include <iostream>
using namespace std;

int main () {
  double a,b,c;
  a = 3.1415926534;
  b = 2006.0;
  c = 1.0e-10;
  cout.precision(5);
  cout <<   a << '\t' << b << '\t' << c << endl;
  cout <<   fixed    << a << '\t' << b << '\t' << c << endl;
  cout << scientific << a << '\t' << b << '\t' << c << endl;
  return 0;
}




The execution of this example displays something similar to:

3.1416          2006            1e-010
3.14159         2006.00000      0.00000
3.14159e+000    2.00600e+003    1.00000e-010