TOpenCLVector::NormL2 Method

Overload List

#	Signature	Description
1	double NormL2(TOpenCLMtxVec Vec, bool* RelativeError = false);	The L2-norm.
2	double NormL2(TOpenCLMtxVec Vec, int* VecIndex, int Index, int Len, bool RelativeError = false);	Calculates the L2 norm \|\|V-Vec\|\| between Vec elements [VecIndex]..[VecIndex+Len-1] and calling vector elements [Index]..[Index+Len-1].
3	double NormL2();	Calculate the L2-norm of the calling vector.
4	double NormL2(int Index, int Len);	Calculates the L2 norm from calling vector elements [Index]..[Index+Len-1].

Overload 1: double NormL2(TOpenCLMtxVec *Vec, bool RelativeError = false);

The L2-norm.

#	Name	Type	Description
1	Vec	TOpenCLMtxVec *
2	RelativeError = false	bool

Returns: L2 norm, defined by ||V-Vec||, where V is calling vector.

Remarks:

If the NormL2 is called without any parameters, the NormL2 calculates the norm of calling vector. The L2 norm of ||V-Vec|| is defined by the formula:

\|\text{V} - \text{Vec}\| _{L2} = \sqrt{\sum _{k=0} ^{\text{Length}-1}\left(|\text{V}[k]-\text{Vec}[k]| \right)^2}

If RelativeError is true then the computed norm is divided by the norm of V, and the function returns the "relative error":

\frac{\| \text{V} - \text{Vec}\|}{\|\text{V}\|}

Examples

#include "Units.clMtxVec.h"
#include "clMtxVec.h"

using namespace Dew;
using namespace Dew::Math;
using namespace Dew::Math::Units::ClMtxVec;

void Example()
{
    TOpenCLVector *a, *b;
    CreateIt(a, b);
    a->CopyFromArray(DewArray<double>{1,2,3,4});
    a->CopyFromArray(DewArray<double>{4,3,2,1});
    double c = a->NormL2(b,true);
    FreeIt(a,b);
}

See Also: TOpenCLVector::NormC, TOpenCLVector::NormL1

Declared in Dew::Math::TOpenCLMtxVec · Dew.Math/clMtxVec.h · Cross-compiler

Overload 2: double NormL2(TOpenCLMtxVec *Vec, int VecIndex, int Index, int Len, bool RelativeError = false);

Calculates the L2 norm ||V-Vec|| between Vec elements [VecIndex]..[VecIndex+Len-1] and calling vector elements [Index]..[Index+Len-1].

#	Name	Type
1	Vec	TOpenCLMtxVec *
2	VecIndex	int
3	Index	int
4	Len	int
5	RelativeError = false	bool

Declared in Dew::Math::TOpenCLMtxVec · Dew.Math/clMtxVec.h · Cross-compiler

Overload 3: double NormL2();

Calculate the L2-norm of the calling vector.

Returns: L2 norm, defined by: NormaL2 = ( Sum(|a[i]|^2) )^0.5 , 0 < i < Length-1 .

Declared in Dew::Math::TOpenCLMtxVec · Dew.Math/clMtxVec.h · Cross-compiler

Overload 4: double NormL2(int Index, int Len);

Calculates the L2 norm from calling vector elements [Index]..[Index+Len-1].

#	Name	Type	Description
1	Index	int
2	Len	int

Declared in Dew::Math::TOpenCLMtxVec · Dew.Math/clMtxVec.h · Cross-compiler