Getting duration value as double

Question

Let's say, I have following duration value:

auto duration=12h+15min+99s+99ms;

I want to know how many hours that is (as double value).

When I do auto hours=std::chrono::duration_cast<std::chrono::hours>(duration), I get hours.count() which is int. What is the right way to get the value for the whole duration expressed as double?

Answer 1

using namespace std::chrono;

// Create a double-based hours duration unit
using dhours = duration<double, hours::period>;

// Assign your integral-based duration to it
dhours h = 12h+15min+99s+99ms;

// Get the value
cout << h.count();

Or alternatively, simply divide your integral based duration by one double-based hours:

cout << (12h+15min+99s+99ms)/1.0h << '\n';