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cross_product.hpp which is now splitted into cross_product (the real) and determinant

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[SVN r76895]
This commit is contained in:
Barend Gehrels
2012-02-05 11:18:51 +00:00
parent b924314228
commit cd84ffd149
1 changed files with 0 additions and 70 deletions
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70
include/boost/geometry/arithmetic/cross_product.hpp
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@@ -71,30 +71,6 @@ struct cross_product<P1, P2, 3>
}
};
template <typename ReturnType, typename U, typename V>
class cross_product2
{
template <typename T>
static inline ReturnType rt(T const& v)
{
return boost::numeric_cast<ReturnType>(v);
}
public :
// Most common dimension, as also defined by Wolfram:
// http://mathworld.wolfram.com/CrossProduct.html
// "In two dimensions, the analog of the cross product for u=(u_x,u_y) and v=(v_x,v_y) is
// uxv = det(uv)
// = u_x v_y - u_y v_x"
static inline ReturnType apply(U const& ux, U const& uy
, V const& vx, V const& vy)
{
return rt(ux) * rt(vy) - rt(uy) * rt(vx);
}
};
} // namespace detail
#endif // DOXYGEN_NO_DETAIL
@@ -129,52 +105,6 @@ inline P1 cross_product(P1 const& p1, P2 const& p2)
}
/*!
\brief Computes the cross product of two vectors, version for four values
\details Because we often have the four coordinate values (often differences)
available, it is convenient to have a version which works directly on these,
without having to make a (temporary) Point or Vector
\ingroup arithmetic
\return the cross product value
*/
template <typename ReturnType, typename U, typename V>
inline ReturnType cross_product2(U const& ux, U const& uy
, V const& vx, V const& vy)
{
return detail::cross_product2
<
ReturnType, U, V
>::apply(ux, uy, vx, vy);
}
// Synonym, because yes, sometimes the algorithm calls it "determinant"
template <typename ReturnType, typename U, typename V>
inline ReturnType determinant(U const& ux, U const& uy
, V const& vx, V const& vy)
{
return detail::cross_product2
<
ReturnType, U, V
>::apply(ux, uy, vx, vy);
}
// TEMPORARY, to be harmonized with cross_product
template <typename ReturnType, typename U, typename V>
inline ReturnType cross_product2(U const& u, V const& v)
{
BOOST_CONCEPT_ASSERT( (concept::ConstPoint<U>) );
BOOST_CONCEPT_ASSERT( (concept::ConstPoint<V>) );
return detail::cross_product2
<
ReturnType,
typename geometry::coordinate_type<U>::type,
typename geometry::coordinate_type<V>::type
>::apply(get<0>(u), get<1>(u), get<0>(v), get<1>(v));
}
}} // namespace boost::geometry
#endif // BOOST_GEOMETRY_ARITHMETIC_CROSS_PRODUCT_HPP