cgal/Algebraic_foundations/doc_tex/Algebraic_foundations_ref/RealEmbeddable.tex

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\begin{ccRefConcept}{RealEmbeddable}
\ccDefinition
A model of this concepts represents numbers that embeddable onto the real
axis. The type obeys the algebraic structure and compares two values according
to the total order of the real numbers.
Remark:\\
If a number type is a model of both IntegralDomainWithoutDiv and
RealComparable, the number an object of that type represents for the
algebraic operations must be the same real number it represents for
comparison. It follows that the ring represented by such a number type
is a subring of the real numbers and hence has characteristic zero
( see http://mathworld.wolfram.com/CharacteristicField.html ).
\ignore{
In addition to the comparison operators, the template class
NiX::NT_traits<NT> provides three adaptable functors for number types
NT that are a model of RealComparable.
* NiX::NT_traits::Abs ()(x) is an AdaptableUnaryFunction that accepts
a number x and computes its absolute value.
* NiX::NT_traits::Sign ()(x) is an AdaptableUnaryFunction that accepts
a number x and computes its three-valued sign.
* NiX::NT_traits::Compare ()(x,y) is an AdaptableBinaryFunction that
accepts two numbers x and y and computes a three-valued comparison result.
* NiX::NT_traits::To_double ()(x) is an AdaptableUnaryFunction that
accepts a number x and computes a double approximation of x.
* NiX::NT_traits::To_Interval ()(x) is an AdaptableUnaryFunction that
accepts a number x and computes a double Interval approximation of x. It
is guaranteed that x is contained in the interval.
}
\ccRefines
\ccc{LessThanComparable}
\ccOperations
\ccFunction{bool operator< (const RealEmbeddable &a,
const RealEmbeddable &b);}{}
\ccGlue
\ccFunction{bool operator<=(const RealEmbeddable &a,
const RealEmbeddable &b);}{}
\ccGlue
\ccFunction{bool operator> (const RealEmbeddable &a,
const RealEmbeddable &b);}{}
\ccGlue
\ccFunction{bool operator>=(const RealEmbeddable &a,
const RealEmbeddable &b);}{}
\ccGlue
\ccSeeAlso
\ccRefIdfierPage{RealEmbeddableTraits}\\
\ccHasModels
\end{ccRefConcept}