Re: [Boost-users] getting started with Boost::Units

Subject: Re: [Boost-users] getting started with Boost::Units
From: Matthias Schabel (boost_at_[hidden])
Date: 2009-01-09 14:16:45

> Thanks!
>
> Why does the the following simple code output "605mi h^-1" instead  
> of "605 mi/h"? Why is the "^-1" at the end?
>
> #include <iostream>
> #include <boost/units/base_units/us/mile.hpp>
> #include <boost/units/base_units/metric/hour.hpp>
> #include <boost/units/io.hpp>
>
> using namespace boost::units;
> using namespace std;
>
> typedef us::mile_base_unit::unit_type mile_unit;
> typedef metric::hour_base_unit::unit_type hour_unit;
> typedef divide_typeof_helper<mile_unit, hour_unit>::type  
> miles_per_hour;
>
> int main() {
>  quantity<miles_per_hour> mph = 605.0 * miles_per_hour();
>  cout << mph << endl;
>  return 0;
> }

The output code does not give special status to exponents of -1, but  
just treats them consistently. If you want specialized output, see  
examples/composite_output.cpp for an example.

Matthias