Manual Search Using Binary Chop

The Problem To Be Solved.

A good friend of mine had found that an Excel spread sheet no longer had a formulae in a particular cell. It had a number there instead. This meant that any changes in other cells associated with the missing formulae had no effect on the result in the TOTAL column. On a regular basis my friend had sensibly made a backup of the spread sheet and now my friend had a great number of them. It was imperative that my friend found out when the formulae had gone missing. My friend was about to conduct a manual search and work through all the backups to find the time when the formulae was last used in the spread sheet. Looking at every backup would have given my friend a lot of work. So I advised using a “Binary Chop” method to make it easy. See Example 4 in particular. Continue reading “Manual Search Using Binary Chop”

The Faster-than-Fast Fourier Transform

Improving The Fast Fourier Transform

The Faster-than-Fast Fourier Transform can replace the Fast Fourier Transform to save processing time when digitising an analogue signal.

For a large range of practically useful cases, MIT researchers find a way to increase the speed of one of the most important algorithms in the information sciences. – Larry Hardesty, MIT News Office.

You can read it all here: MIT News Office.

Well this might be the case but it could so easily be that everyone takes it at face value and embodies this algorithm into all new electronic sound and video processors. We may then find all our music and video content degraded as a consequence. Then it will be too late. With the Faster-than-Fast Fourier Transform processing sound and video is quicker and cheaper so we’ll be stuck with it. Musicians who prefer analogue sound reproduction may find this degrades digital sound further. On the other hand it could improve the quality.