TMtx::DetectMtxType Method

TMtxType DetectMtxType(bool CheckPosDef = false);

Determines type of the matrix.

#	Name	Type	Description
1	CheckPosDef = false	bool

Remarks:

Tests the calling matrix and returns the TMtxType of the calling of matrix. The following types are supported:

TMtxType::mtSymmPosDef = symmetric positive definite matrix
TMtxType::mtSymmetric = symmetric matrix
TMtxType::mtHermPosDef = Hermitian positve definite matrix
TMtxType::mtHermitian = Hermitian matrix
TMtxType::mtTriangle = triangular matrix, with unit or non unit main diagonal
TMtxType::mtGeneral = general matrix (none of the above)

Checking for positive definite matrix can be very expensive (O(n) = 1/3*n^3). Therefore the ChekPosDef parameter is False by default, unless the user specifies otherwise. The method will not detect banded matrix storage.

Examples

#include "MtxVec.h"
#include "Units.MtxVec.h"

using namespace Dew;
using namespace Dew::Math;
using namespace Dew::Math::Units::MtxVec;

void Example()
{
    TVec *X, *B;
    TMtx* A;
    TMtxType at;

    CreateIt(X, B);
    CreateIt(A);
    B->SetIt(false, DewArray<double>{0, 2});
    A->SetIt(2, 2, false, DewArray<double>{1, 2,
        2, 4});  // 2x2 real matrix

    at = A->DetectMtxType();
    A->LUSolve(B, X, at);
    // This is the same for this example (except slower)
    A->LUSolve(B, X, TMtxType::mtSymmetric);
    // You could also specify
    A->AutoMtxType = true;
    A->LUSolve(B, X);  // the type is autodetected
    FreeIt(B, X);
    FreeIt(A);
}

Declared in Dew::Math::TMtx · Dew.Math/MtxVec.h · Cross-compiler