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details Mathematical Functions VIGRA


Classes

class  BSpline
class  BSplineBase
class  CatmullRomSpline
class  CoscotFunction
class  Gaussian

Functions

template<class T> double erf (T x)
template<class T> NumericTraits< T >::Promote sq (T t)
template<class T> T sign (T t)
template<class T1, class T2> T1 sign (T1 t1, T2 t2)
template<typename IntType> IntType gcd (IntType n, IntType m)
template<typename IntType> IntType lcm (IntType n, IntType m)
result_type operator() (argument_type x) const


Detailed Description


Useful mathematical functions and functors.


Function Documentation


double erf   x

 

The error function.

With the exception of Solaris (where erf() is provided as an extension of the C math library), VIGRA implements erf() as an approximation of the error function

according to the formula given in Press et al. "Numerical Recipes".

#include "vigra/mathutil.hxx"
Namespace: vigra


IntType gcd IntType    n,
IntType    m

 

Calculate the greatest common divisor.

This function works for arbitrary integer types, including user-defined (e.g. infinite precision) ones.

#include "vigra/rational.hxx"
Namespace: vigra


IntType lcm IntType    n,
IntType    m

 

Calculate the lowest common multiple.

This function works for arbitrary integer types, including user-defined (e.g. infinite precision) ones.

#include "vigra/rational.hxx"
Namespace: vigra


CatmullRomSpline< T >::result_type operator() argument_type    x const [inherited]

 

function (functor) call


T1 sign T1    t1,
T2    t2

 

The binary sign function.

Transfers the sign of t2 to t1.

#include "vigra/mathutil.hxx"
Namespace: vigra


T sign   t

 

The sign function.

Returns 1, 0, or -1 depending on the signm of t.

#include "vigra/mathutil.hxx"
Namespace: vigra


NumericTraits<T>::Promote sq   t [inline]

 

The square function.

sq(x) is needed so often that it makes sense to define it as a function.

#include "vigra/mathutil.hxx"
Namespace: vigra

© Ullrich Köthe (koethe@informatik.uni-hamburg.de)
Cognitive Systems Group, University of Hamburg, Germany

html generated using doxygen and Python
VIGRA 1.3.2 (27 Jan 2005)