Re: [Boost-users] [Boost.polygon.voronoi] [Boost.multiprecision] higher precision voronoi

Subject: Re: [Boost-users] [Boost.polygon.voronoi] [Boost.multiprecision] higher precision voronoi
From: Steven Watanabe (watanabesj_at_[hidden])
Date: 2014-03-17 13:32:36

AMDG

On 03/17/2014 08:57 AM, Weatherby,Gerard wrote:
> 
>> 
>> Had polygon been coded like this:
>>
>> template <typename T>
>> T get_sqrt(const T& that) {
>>     using std::sqrt;
>>     return (sqrt)(that); // ADL is now active }
>>
>> Then the correct overload would have been found.
>>

Not quite true.  The parentheses disable ADL,
just as much as using a qualified name.  To
prevent macro expansion of sqrt while enabling
ADL, you need to use:

sqrt BOOST_PREVENT_MACRO_SUBSTITUTION (that)

>> <snip>
> 
> I tried both suggestions as best I understood them; changing the boost::polygon::voronoi get_sqrt implementation and changing
> my code as follows. (Aside: I realized I actually wanted 80, not 48 floating point bits).
> 
> namespace bmulti = boost::multiprecision;
>    using bmulti::et_off;
>     typedef bmulti::number<bmulti::cpp_dec_float<80>,et_off> floatingType;
> 

Note: cpp_dec_float<80> has 80 /decimal/ digits, not 80 bits.

> But still got:
> 1>d:\workspace\movingboundary\boost_1_53_0\boost\polygon\detail\voronoi_robust_fpt.hpp(61): error C2665: 'sqrt' : none of the 3 overloads could convert all the argument types

In Christ,
Steven Watanabe