chrono duration_cast metodu

Örnek - high_resolution_clock
Şöyle yaparız.

boost::chrono::high_resolution_clock::time_point t0, t1;
  t0 = boost::chrono::high_resolution_clock::now();

...

t1 = boost::chrono::high_resolution_clock::now();

auto t1_t0 = t1 - t0;

auto nsec = boost::chrono::duration_cast<boost::chrono::seconds>(t1_t0);