Online Math Equation Latex Editor: Codecogs

https://www.codecogs.com/latex/eqneditor.php

codecogscom has made an online equation editor for those that want to make math equations using the LaTeX code format using the MathML library.  Output formats include graphics lie GIFs, HTML and URLs to their website.

This is good for sites like stack exhange mathematics.

Viewing Wikipedia Math equations on Firefox

Wikipedia has promptly and unceremoniously dropped mathJAX support for wiki pages. For those of us that read math equations this can be a problem. They brought in MathML which is a mark-up version but not everyone can get the images that are sent instead of the equations mathJAX used to convert. If you work somewhere that rejects / filters incoming images for safety reasons then you need a way to convert; just like mathJAX did way back in June 2015.



Scouring the Firefox addons I found a solution.

To see the equations in the new Wikipedia, download this plugin:

Wiki Math Converter

It produced this output

${\text{𝐶𝑀𝐴}}_{n+1}=\frac{x_{n+1}+n\cdot {\text{𝐶𝑀𝐴}}_n}{n+1}$

Technology Readiness Levels -TRL

NASA developed a system / model if you will to describe the readiness of a piece of technology for application.

These technical / application based levels describe how finished a "finished product" is.

http://www.hq.nasa.gov/office/codeq/trl/trlchrt.pdf

When you are trying to decide how ready a piece of technology is for application, you might want to use these levels for yourself. Adopting common conventions like this makes it easier to describe your work in a way others not familiar with can understand by common reference. I am on a big kick for interoperability these days, using common definitions and conventions makes sense in so many ways. Less confusion, more understanding.

Make Archve From Folder

I wrote a simple - too simple - and poorly written shell script to make an archive file out of a directory containing the name of the computer, the date including hours,  and the project name.

#!/bin/bash
# make archive folder DRE 2015
# Description: makes a named folder and archives it from a GNU Autotools
#specific CVS env vars
#export CVS_RSH=ssh
#export DIR=/usr/local/cvsroot
#export CVSROOT=:pserver:dave@dogma:$DIR

#clean out files if program
make distclean
# remove old copies of archives
rm -fr *.tar.gz

#create dated folder for new mods
storedate=$(date -Ihours)
project=$(printf '%q\n' "${PWD##*/}")
name=$(uname -n)

total="$storedate-$project-$name"
mkdir "$total"
cd "$total"
cp -r  ../* .
rm -fr "$total"
cd ..
tar -czf "$total.tar.gz" "$total"

It isn't the wisest script but people forget the point of unix.  It wasn't to be masters of all aspects of the operating system and tools, but to make the computer do the work so the human didn't have to. I did a quick search for the proper way to copy a folder without itself in the new folder.  I wasn't  happy with what I found so I just used basic commands I knew would work. I don't need to be expert to get it to work. That is a big stumbling block still with Unix. Usability. Knowing the perfect way to do something isn't important as most people assume.

This will waste the computers time executing extra commands.  But so what? It idles 90+% of the time when I am web browsing. It's not in a hurry. I am.

http://andrew.gibiansky.com/blog/physics/quadcopter-dynamics/

http://andrew.gibiansky.com/blog/physics/quadcopter-dynamics/

How you know your Free or Open Source Software Project is doomed to FAIL

http://spot.livejournal.com/308370.html

Fix your drone; fix landing gear.

Ok so I bought a Horizon hobby Blade 180QX quadcopter and flew it for a few days  before  I smashed it.

The landing gear is too weak for the height this quadcopter falls from.  The major complaint I have is that without cross bracing it buckles if the quadcopter lands sideways and bends in the skids as shown in photo below.

To fix it. You can replace it which is a $5 part.  But then that doesn't change the outcome.

 You want landing gear to absorb the shock but not fold up easily. You will have more down time and less flying with weak original landing gear.

 Notice how bent in the gear are from original to new ones. I went to Michaels here in Chandler Arizona and bought 2 foot 1/8 th inch dowells and some loctite.  I cut two braces and glued them to a new landing gear.  Dry and then install to underchassis.

 Scissors work fine to score and snap dowells and clean the edges.

 Gelled loctite works fast so you can set both and movertical on.

 There the cross braves are added to mske landing transfer more force without snapping the gear.