Re: [Boost-users] Using atan2 in boost::units

Subject: Re: [Boost-users] Using atan2 in boost::units
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2010-01-04 11:10:27

AMDG

Brandon Olivares wrote:
> I need to use the boost::units::atan2() function in boost/units/cmath.hpp,
> but am having trouble figuring out how. Do the units have to be
> dimensionless, or can they be any unit?
>
> I have two variables, x_ and y_ which are of a scaled unit type, called
> light_second_unit. I'm calling it like this:
>
> boost::units::atan2(y_, x_);
>
> I get this error:
>
> ./physics/cartesian_coordinate_system/point.cpp:85: error: no matching
> function for call to
> `atan2(boost::units::quantity<boost::units::astronomical::light_second_unit,
> double>,
> boost::units::quantity<boost::units::astronomical::light_second_unit,
> double>)'
>
> If it has to be dimensionless, how do I convert them to a dimensionless
> quantity?
>   

The problem is that the library tries to determine the
return type from the system.  In this case, the system
doesn't include a unit of angle, so the call fails.

In Christ,
Steven Watanabe