vigra - template<> struct SquareRootTraits<ArithmeticType>

template<> struct SquareRootTraits<ArithmeticType>

Unary traits for the calculation of the square root of arithmetic objects.

This traits class is used to determine appropriate argument and result types for the function sqrt(). These traits are typically used like this:

ArithmeticType t = ...;
SquareRootTraits<ArithmeticType>::SquareRootResult r = 
      sqrt((SquareRootTraits<ArithmeticType>::SquareRootArgument)t);

This approach avoids 'ambiguous overload errors' when taking the square root of an integer type. It also takes care of determining the proper result of the sqrt() function of vigra::FixedPoint and of the norm() function, when it is implemented via sqrt(squaredNorm(x)). The following members are defined in SquareRootTraits<ArithmeticType>:

`typedef ArithmeticType Type;`	the type itself
`typedef ... SquareRootArgument;`	required argument type for srqt(), i.e. `sqrt((SquareRootArgument)x)`
`typedef ... SquareRootResult;`	result of `sqrt((SquareRootArgument)x)`

NormTraits for the built-in types are defined in #include <vigra/numerictraits.hxx>

Namespace: vigra