print double numbers in binary form

print_double_binary.cpp

#include <iostream>
#include <bitset>
#include <limits>

//
// Print double numbers in binary form
//

typedef std::numeric_limits<double> dbl;

using namespace std;

typedef union {
   unsigned long long u;
   double d;
} dfloat;

int main() {
   dfloat x, y, z;
   x.d = 0.1234567890123455l;
   y.d = x.d * 10.0;
   z.d = x.d * 10000000000000000.0l;

   cout.precision(dbl::digits10);
   cout << "x(dec): " << fixed << x.d << endl;
   cout << "x(bin): " << bitset<64>(x.u) << endl;
   cout << "y(dec): " << fixed << y.d << endl;
   cout << "y(bin): " << bitset<64>(y.u) << endl;
   cout << "z(dec): " << fixed << z.d << endl;
   cout << "z(bin): " << bitset<64>(z.u) << endl;
   return 1;
}

// http://stackoverflow.com/questions/7349689/c-how-to-print-using-cout-the-way-a-number-is-stored-in-memory
// http://stackoverflow.com/questions/8521638/exact-binary-representation-of-a-double
// http://stackoverflow.com/questions/554063/how-do-i-print-a-double-value-with-full-precision-using-cout