APC Smart UPS 750 battery replacement notes

Introduction This post continues my notes on Smart UPS 750, three years later, when it was time to replace the batteries (because they barely held for 13 minutes). It should have been simple, but if I wrote this lengthy post about it, there was clearly something going on. Note that UPSes and their batteries is [...]

Using firejail to throttle network bandwidth for wget and such

Introduction Occasionally, I download / upload huge files, and it kills my internet connection for plain browsing. I don’t want to halt the download or suspend it, but merely calm it down a bit, temporarily, for doing other stuff. And then let it hog as much as it want again. There are many ways to [...]

Octave: Creating images from plots for web page

This should have been a trivial task, but it turned out quite difficult. So these are my notes for the next time. Octave 4.2.2 under Linux Mint 19, using qt5ct plugin with GNU plot (or else I get blank plots). So this is the small function I wrote for creating a plot and a thumbnail: [...]

Looping on file wildcards in Octave

So I have written a function, showfile() for Octave 4.2.2 on Linux, which accepts a file name as its argument. And now I want to run it on all files in the current directory that match a certain pattern. How? So first, obtain the list of files, and put it in a variable: >> x=ls(‘myfiles*.dat’); [...]