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Adding another way to make a Root_of_2 in the case you already know that delta is not zero

This commit is contained in:
Pedro Machado Manhaes de Castro 2006-06-23 11:39:09 +00:00
parent c089992a3d
commit 02a16a1a8b
1 changed files with 54 additions and 0 deletions
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54
Number_types/include/CGAL/make_root_of_2.h
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@ -71,6 +71,34 @@ namespace CGALi {
return make_root_of_2(a_,b_,c_,smaller);
}
// This version is internal and can be re-used for
// number types which are rational.
template < typename RT, typename FT >
Root_of_2< RT >
make_root_of_2_rational(const FT &a, const FT &b, const FT &c, bool smaller,
bool dinz)
{
typedef CGAL::Rational_traits< FT > Rational;
Rational r;
// CGAL_assertion( r.denominator(a) > 0 );
// CGAL_assertion( r.denominator(b) > 0 );
// CGAL_assertion( r.denominator(c) > 0 );
/* const RT lcm = ( r.denominator(a) * r.denominator(b) * r.denominator(c) )/
( gcd( r.denominator(a), gcd(r.denominator(b), r.denominator(c)) ) );
RT a_ = r.numerator(a) * ( lcm / r.denominator(a) );
RT b_ = r.numerator(b) * ( lcm / r.denominator(b) );
RT c_ = r.numerator(c) * ( lcm / r.denominator(c) );
*/
RT a_ = r.numerator(a) * r.denominator(b) * r.denominator(c);
RT b_ = r.numerator(b) * r.denominator(a) * r.denominator(c);
RT c_ = r.numerator(c) * r.denominator(a) * r.denominator(b);
return make_root_of_2(a_,b_,c_,smaller,dinz);
}
// automatic dispatcher between the 2 generic versions (using Root_of_2 or
// sqrt()), if sqrt() exists (checking Has_sqrt).
@ -80,11 +108,19 @@ struct Make_root_of_2_helper
{
typedef Root_of_2<RT> result_type;
result_type operator()(const RT& a, const RT& b, const RT& c, bool smaller,
bool dinz)
const
{
return Root_of_2<RT>(a, b, c, smaller, dinz);
}
result_type operator()(const RT& a, const RT& b, const RT& c, bool smaller)
const
{
return Root_of_2<RT>(a, b, c, smaller);
}
};
// Specialization for Has_sqrt == Tag_true
@ -93,11 +129,19 @@ struct Make_root_of_2_helper <RT, Tag_true>
{
typedef RT result_type;
result_type operator()(const RT& a, const RT& b, const RT& c, bool smaller,
bool dinz)
const
{
return CGALi::make_root_of_2_sqrt(a, b, c, smaller);
}
result_type operator()(const RT& a, const RT& b, const RT& c, bool smaller)
const
{
return CGALi::make_root_of_2_sqrt(a, b, c, smaller);
}
};
} // namespace CGALi
@ -112,6 +156,16 @@ make_root_of_2(const RT &a, const RT &b, const RT &c, bool smaller)
return CGALi::Make_root_of_2_helper<RT>()(a, b, c, smaller);
}
template < typename RT >
inline
typename CGALi::Make_root_of_2_helper<RT>::result_type
make_root_of_2(const RT &a, const RT &b, const RT &c, bool smaller,
bool dinz)
{
CGAL_assertion( a != 0 );
return CGALi::Make_root_of_2_helper<RT>()(a, b, c, smaller, dinz);
}
} // namespace CGAL
#endif // CGAL_MAKE_ROOT_OF_2_H