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Hi,

I want to have cholski decomposition of a matrix. In opencv doc is here and I think this doc is still good. In following program I try to have cholesky decomposition of matrix A

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;
using namespace std;


int main (int argc,char **argv)
{

    Mat m1=(Mat_<double>(3,3) << 4,12,-16,12,37,-43,-16,-43,98);

    cout<<m1<<endl;
    Cholesky ((double*)m1.ptr(),m1.cols*8, 3,NULL, 0, 0);
    m1.at<double>(0,1)=0;m1.at<double>(0,2)=0;m1.at<double>(1,2)=0;
    cout<<"L = "<<m1<<endl;
    cout<<"L' = "<<m1.t()<<endl;
    cout << "LL'="<<m1.mul(m1.t())<<endl;
}

Result is

A=[4, 12, -16;
 12, 37, -43;
 -16, -43, 98]
L = [0.5, 0, 0;
 6, 1, 0;
 -8, 5, 0.3333333333333333]
L' = [0.5, 6, -8;
 0, 1, 5;
 0, 0, 0.3333333333333333]
LL'=[0.25, 0, -0;
 0, 1, 0;
 -0, 0, 0.1111111111111111] <> A

Is it a bug or I miss something?

Hi,

I want to have cholski decomposition of a matrix. In opencv doc is here and I think this doc is still good. In following program I try to have cholesky decomposition of matrix A

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;
using namespace std;


int main (int argc,char **argv)
{

    Mat m1=(Mat_<double>(3,3) << 4,12,-16,12,37,-43,-16,-43,98);

    cout<<m1<<endl;
    Cholesky ((double*)m1.ptr(),m1.cols*8, 3,NULL, 0, 0);
    m1.at<double>(0,1)=0;m1.at<double>(0,2)=0;m1.at<double>(1,2)=0;
    cout<<"L = "<<m1<<endl;
    cout<<"L' = "<<m1.t()<<endl;
    cout << "LL'="<<m1.mul(m1.t())<<endl;
"LL'="<<m1*m1.t()<<endl;
}

Result is

A=[4, 12, -16;
12, 37, -43;
-16, -43, 98]
L = [0.5, 0, 0;
6, 1, 0;
-8, 5, 0.3333333333333333]
L' = [0.5, 6, -8;
0, 1, 5;
0, 0, 0.3333333333333333]
LL'=[0.25, 0, -0;
0, 1, 0;
-0, 0, 0.1111111111111111] 3, -4;
3, 37, -43;
-4, -43, 89.11111111111111] <> A

Is it a bug or I miss something?

Hi,

I want to have cholski decomposition of a matrix. In opencv doc is here and I think this doc is still good. In following program I try to have cholesky decomposition of matrix A

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;
using namespace std;


int main (int argc,char **argv)
{

    Mat m1=(Mat_<double>(3,3) << 4,12,-16,12,37,-43,-16,-43,98);

    cout<<m1<<endl;
    Cholesky ((double*)m1.ptr(),m1.cols*8, 3,NULL, 0, 0);
    m1.at<double>(0,1)=0;m1.at<double>(0,2)=0;m1.at<double>(1,2)=0;
    cout<<"L = "<<m1<<endl;
    cout<<"L' = "<<m1.t()<<endl;
    cout << "LL'="<<m1*m1.t()<<endl;
}

Result is

 A=[4, 12, -16;
-16;  12, 37, -43;
-16, -43; -16,
-43, 98]
98]
L = [0.5, 0, 0;
0;  6, 1, 0;
0;  -8, 5, 0.3333333333333333]
0.3333333333333333] L' = [0.5, 6, -8;
-8;  0, 1, 5;
0, 0, 0.3333333333333333]
5; 0, 0,
0.3333333333333333]
LL'=[0.25, 3, -4;
-4;  3, 37, -43;
-43;  -4, -43, -43,
89.11111111111111] <> A
A

Hi,

I want to have cholski choelsky decomposition of a matrix. In opencv doc is here and I think this doc is still good. In following program I try to have cholesky decomposition of matrix A

#include <opencv2/opencv.hpp>
#include <iostream>

using namespace cv;
using namespace std;


int main (int argc,char **argv)
{

    Mat m1=(Mat_<double>(3,3) << 4,12,-16,12,37,-43,-16,-43,98);

    cout<<m1<<endl;
    Cholesky ((double*)m1.ptr(),m1.cols*8, 3,NULL, 0, 0);
    m1.at<double>(0,1)=0;m1.at<double>(0,2)=0;m1.at<double>(1,2)=0;
    cout<<"L = "<<m1<<endl;
    cout<<"L' = "<<m1.t()<<endl;
    cout << "LL'="<<m1*m1.t()<<endl;
}

Result is

 A=[4, 12, -16;  12, 37, -43;  -16,
-43, 98] 
L = [0.5, 0, 0;  6, 1, 0;  -8, 5, 0.3333333333333333] L' = [0.5, 6, -8;  0, 1, 5;  0, 0,
 0.3333333333333333] 
LL'=[0.25, 3, -4;  3, 37, -43;  -4, -43,
 89.11111111111111] <> A

Is it a bug or I miss something?