ChapterZero

My officemate asked me a Matlab question that’s worthy of consideration: what is a fast method for locating a submatrix within a matrix? In his case, we were dealing with two dimensional matrices, but to make it more challenging, attempt it with matrices of arbitrary dimension.

Some history: I coded a solution to this problem during my undergraduate research, to use in registering biomedical volumes. When I started working on the project, there were some reference subvolumes that had been extracted from various volumes, and exactly where they’d been extracted from had been lost. The data sets were relatively large, so the code had to be fast … too bad I can’t recall my solution off the top of my head.

It’d be intereresting to compare the performance of various solutions. I’ll try to recreate mine.

Possibly relevant posts:

• pseudo3d navigation (1/1/2006)
• Axiom vs other CASes (12/18/2003)
• Topologies out the wazoo! (3/24/2006)