HDFView improvements

HDFView is a Java-based application to view, create, and modify HDF5 files in a tabular format. HDFView can also make 1-D (line) plots and 2-D (raster) plots of the data in an HDF5 file. For example data see Neon.

To view a plot of data, right click on the dataset name and select “Open As” and then set the parameters to view the data. It’s important to use a recent version of HDFView, as a long-time issue especially with Linux distributions is having old, broken versions of HDFView. A typical problem with old HDFView versions is that HDFView won’t start.

LaTeX syntax highlight with Minted

LaTeX code highlighting is possible using the “minted” package, which uses Pygments as a backend. To install minted:

tlmgr install minted

python -m pip install pygments

If using a GUI, the “–shell-escape” option may need to be added. In TeXmaker / TeXstudio, under “Options → Configure → Commands” add --shell-escape right after the compiler executable.

Install Tikz with TeXLive

When using TeXLive, the “tlmgr” program allows installing many LaTeX-related packages. For example, to enable Tikz diagrams via \usepackage{tikz}, install the “pgf” package:

tlmgr install pgf

Packages can also be added to TeXLive by the GUI TeX Live Manager. Under Package List select Status: All.

LaTeX bibliography clickable URLs

Generally LaTeX bibliographies can use clickable URLs if the LaTeX document specifies:


and for software, data, etc. entries that don’t have a specific type in the bibliography style:

author={lorem ipsum},

Note that HTML percent “%” codes do not work. The HTML percent must be translated to their ASCII character. For example, %3A is “:” colon.

macOS Airport WiFi information

For many years the undocumented macOS command-line utility named “airport” (not to be confused with the Airport Utility app) gives detailed information about the current WiFi connection and nearby WiFi APs. This utility is made easily available by setting the alias:

alias airport=/System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport

The current WiFi connection details are given by:

airport -I

The current WiFi channel and bandwidth are given like:

channel: 1,20

where “1” is the channel number and “20” is the bandwidth in MHz.

Determining current BSSID requires using “sudo”, which doesn’t resolve the alias. Reveal BSSID and other advanced details like:

sudo /System/Library/PrivateFrameworks/Apple80211.framework/Versions/Current/Resources/airport -I

Return data in machine-readable XML format by adding option “-x”. This is used in our MozLoc WiFi-based location program.

airport -Ix

Apple laptops from 2023 and newer may have WiFi 6E. Without WiFi 6E hardware, the Apple laptop cannot use the 6 GHz WiFi band.

Windows exit code -1073741819

On Windows computers when upgrading software or simply having left the computer on for a long time, it may suddenly stop working on common programs with exit code “-1073741819”, corresponding to hex code 0x0005. This code means “Access denied”, which can happen when another process has changed or locked particular files needed such as libstdc++ or any other binary file. The simplest and most common fix is to simply reboot the Windows computer, and ensure other programs aren’t auto-loading or locking binary files needed.

Quality USB charging adapters

The world is full of inexpensive USB charging adapters. Since the adapters connect to AC mains power, a very large amount of energy is available that can result in damage to the device or even the home / office the charger is in under catastrophic failure. Since nearly every person in the world needs multiple USB charge adapters, the manufacturers compete aggressively on size and price. This leads the OEMs to be tempted to cut back on safety and interfere-reducing components.

Ethical and responsible manufacturers find a way to keep the quality and safety circuitry intact, and may even go beyond the chip manufacturer and safety regulator requirements. These extra measures help protect the charger brand image. A distinct retailer known for quality USB charger adapters is IKEA. It’s speculated that since they’re putting their own brand on the charger, IKEA is perhaps taking notable care to ensure the chargers don’t damage devices or the surroundings.

Run PowerShell command with environment variable

Unix-like shells typically have a syntax that allows running a command with one or more environment variables having values that don’t persist after the command. For example, in Unix-like shells:

CC=clang CXX=clang++ make

Runs the program “make” with environment variables CC and CXX temporarily set. Subsequent commands use the original value, if any, of CC and CXX.

In PowerShell this syntax doesn’t directly exist, but can be effected like:

pwsh -c { $env:CC="clang"; $env:CXX="clang++"; make }

Another example:


pwsh -c { $env:hi="hello"; python -c "import os; print(os.getenv('hi'))" }

Unix-like shell:

hi="hello" python -c "import os; print(os.getenv('hi'))"

GitHub Actions YaML string comparison

YaML is used by GitHub Actions workflow expressions. The “if” conditional logic for a task uses comparison operators that also work to compare strings, especially useful for version numbers. The relevant portion of an example CI workflow follows:



        release: [R2022a, R2022b, R2023a]


    - name: Run Matlab tests (buildtool)
      if: ${{ matrix.release >= 'R2022b' }}
      uses: matlab-actions/run-build

Disable Windows reporting modal

On Windows, program faults can cause an modal window to appear regarding reporting the issue to Microsoft. This window stops automated scripts from further progress. This is a problem for long-running programs or scripts that call other programs, perhaps on a Task Schedule.

modal Windows popup blocks programs restart

Disable Windows Reporting modal windows on Windows Pro and non-Pro by simply opening “services.msc” and disable “Windows Error Reporting Service”.

Windows Pro only

Alternatively, for Windows Pro:

Press +r and type


Go to Computer ConfigurationAdministrative TemplatesWindows ComponentsWindows Error Reporting and configure as desired.

Group Edit dialog