Skip to main content
7 votes

How can I efficiently find an anti-symmetric generator of a special orthogonal matrix?

As I had noted in comments (now deleted), the problem is when you have eigenvalues equal to $-1$; those must come in pairs, since $\det O = 1$. If $O = \begin{bmatrix}-1 \\ & -1\end{bmatrix}$, ...
Federico Poloni's user avatar
3 votes

How to separate text from the paper on a black and white page?

One could imitate the approach in Dropbox's Blog Post - Fast Document Rectification and Enhancement: $$ \arg \min_{ J \left( x, y \right) } \sum_{x, y} \left\| J \left( x, y \right) - 255 \right\|_{2}^...
Royi's user avatar
  • 390
2 votes

optimize this python code that involves matrix inversion

Since S is SPD, you can (and should) use np.linalg.cholesky to get a cholesky factorization which will be ~2x faster than the LU ...
Oscar Smith's user avatar

Only top scored, non community-wiki answers of a minimum length are eligible