Hello, I want to calculate the eigenvectors to get the second smallest one for segmentation using DGESVD.
My problem is that I don´t know if the order is by columns or rows.
I use the lastrow-1 and I move by columns. Should it be correct?.
for(int j=0;j<nodes;j++){
eigenToProject[j] = (float) evec[nodes-2][j];
}
I thought it was like that but when I used arpack it was by columns and as arpack uses lapack
I am a bit confused. becuase I need both.
Thanks !!