Trans: Latin prefix implying "across" or "Beyond", often used in gender nonconforming situations – Scend: Archaic word describing a strong "surge" or "wave", originating with 15th century english sailors – Survival: 15th century english compound word describing an existence only worth transcending.

Category: Good Ideas (Page 2 of 8)

Convert .heic –> .png

on github here, or just get this script:


Well, following the current course of Apple’s corporate brilliance, iOS now defaults to .heic compression for photos.


Without further delay, let's convert these to png, here from the sanctuary of Bash in ♡Ubuntu Budgie♡.

Libheif is well documented here on Github BTW

# recursively convert .heic to png
# by Jess Sullivan
# permiss:
# sudo chmod u+x
# installs heif-convert via ppa:
# sudo ./
# run as $USER:
# ./

command -v heif-convert >/dev/null || {

  echo >&2 -e "heif-convert not intalled! \nattempting to add ppa....";

  if [[ $EUID -ne 0 ]]; then
     echo "sudo is required to install, aborting."
     exit 1

  add-apt-repository ppa:strukturag/libheif
  apt-get install libheif-examples -y
  apt-get update -y

  exit 0


# default behavior:

for fi in *.heic; do

  echo "converting file: $fi"

  heif-convert $fi $fi.png

 # FWIW, convert to .jpg is faster if png is not required 
 # heif-convert $fi $fi.jpg


D&M Shields – Fusion 360

As of 4/4/20, we are busy 3d printing our rigid shield design, efficiently hacked into its current form by Bret here at D&M. click here to visit or download the Fusion files!

The flat, snap-fit nature of this design can easily be lasercut as well- the varied depths of the printed model are just an effort to minimize excess plastic and print time.

More to come on the laser side of things- in addition to the massive time savings- like <20 seconds vs. >3 hours per shield- we can use far cheaper and varied materials with the addition of our sterilizable and durable UV resins and coatings. Similarly, lasercut stock + resin offers the possibility quick adaptation and derivative design, such as [flexible]( UV cured forms.

When it must be Windows….

Added here on Github

Regarding Windows-specific software, such as ArcMap:

Remote Desktop:
The greatest solution I've settled on for ArcMap use continues to be Chrome Remote Desktop, coupled with an IT Surplus desktop purchased for ~$50. Once Chrome is good to go on the remote Windows computer, one can operate everything from a web browser from anywhere else (even reboot and share files to and from the remote computer). While adding an additional, dedicated computer like this may not be possible for many students, it is certainly the simplest and most dependable solution.

VirtualBox, Bootcamp, etc:
Oracle's VirtualBox is a longstanding (and free!) virtualization software. A Windows virtual machine is vastly preferable over Bootcamp or further partition tomfoolery.
One can start / stop the VM only when its needed, store it on a usb stick, avoid insane pmbr issues, etc.

  • Bootcamp will consume at least 40gb of space at all times before even attempting to function, whereas even a fully configured Windows VirtualBox VDI will only consume ~22gb, and can be moved elsewhere if not in use.
  • There are better (not free) virtualization tools such as Parallels, though any way you slice it a dedicated machine will almost always be a better solution.

Setup & Configure VirtualBox:

There are numerous sites with VirtualBox guides, so I will not go into detail here.

Extra bits on setup-

  • Guest Additions are not necessary, despite what some folks may suggest.

  • Dynamically Allocated VDI is the way to go as a virtual disk. There is no reason not to set the allocated disk size to the biggest value allowed, as it will never consume any more space than the virtual machine actually needs.

  • Best to click through all the other machine settings just to see what is available, it is easy enough to make changes over time.

  • There are many more levels of convoluted not worth stooping to, ranging from ArcMap via AWS EC2 or openstack to KVM/QEMU to WINE. Take it from me


Ubuntu on Captive Portal WiFi


Some distros (Ubuntu and its derivatives on my Macbook for instance) struggle to find a route to the captive portal on public networks (read: Starbucks). Assuming you want to connect the way they intend (via the gateway through the captive portal) because you are a rule abiding patron, all you need to do is visit the address of the gateway. There is no need to fiddle with your network drivers, disable SSL stuff or engage in plebian network tomfoolery.

find and open wifi captive portal (such as Starbucks)
written by Jess Sullivan
from netifaces import gateways
from sys import argv
from time import sleep
import subprocess

help_str = str("\n " +
               'usage: \n ' +
               ' -h : print this message again \n' +
               ' -i : `pip3 install netifaces`  \n' +
               'You may specify a browser argument to complete the portal, such as \n' +

def argtype():
        if len(argv) > 1:
            use = True
        elif len(argv) == 1:
            use = False
            print('command takes 0 or 1 args, use -h for help')
            raise SystemExit
        print('arg error... \n command takes 0 or 1 args, use -h for help')
        raise SystemExit
    return use

def main():

    all_gates = gateways()
    target = all_gates['default'][2][0]

    if argtype():

        if argv[1] == '-h':

        if argv[1] == '-i':
                subprocess.Popen('pip3 install netifaces',
                print('err running pip3 install netifaces')


            print(str('opening portal in ' + argv[1]))
            subprocess.Popen(str(argv[1] + ' ' + str(target)),


        print(str('\n please visit address ' + target +
                  ' in a browser to complete portal setup \n'))


JDK Management in R

Quickly & forcefully manage extra JDKs in base R
Simplify rJava woes

# get this script:

rJava is depended upon by lots of libraries- XLConnect, OpenStreetMap, many db connectors and is often needed while scripting with GDAL.

library(XLConnect)   # YMMV

Errors while importing a library with depending on a JDK are many, but can (usually) be resolved by reconfiguring the version listed somewhere in the error.

On mac OSX (on Mojave at least), check what you have installed here- (as admin, this is a system path) :

sudo ls  "/Library/Java/JavaVirtualMachines/ 

I seem to usually have at least half a dozen or more versions in there, between Oracle and openJDK. Being Java, these are basically sandboxed as JVMs and are will not get in each others way.


Unlike JDK configuration for just about everything else, aliasing or exporting a specific release to $PATH will not cut it in R. The shell command to reconfigure for R-

sudo R CMD javareconf

...seems to always choose the wrong JDK. Renaming, hiding, otherwise trying to explain to R the one I want (lib XLConnect currently wants none other than Oracle 11.0.1) is futile.
The end-all solution for me is usually to temporarily move other JDKs elsewhere.
This is not difficult to do now and again, but keeping a CLI totally in R for moving / replacing JDKs makes for organized scripting.

 JDKmanager help: 
 (args are not case sensitive) 
 (usage: `sudo rscript JDKmanager.R help`) 

 list    :: prints contents of default JDK path and removed JDK path 
 reset   :: move all JDKs in removed JDK path back to default JDK path 
 config ::  configure rJava.  equivalent to `R CMD javareconf` in shell 

 specific JDK, such as 11.0.1, 1.8,openjdk-12.0.2, etc: 
    searches through both default and removed pathes for the specific JDK.  
    if found in the default path, any other JDKs will be moved to the `removed JDKs` directory. 
    the specified JDK will be configured for rJava.
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