Fixing Missing Battery Icon Problem on a Windows 10 Laptop

On a Windows 10 laptop, somehow the battery icon disappeared from the System Tray in the Taskbar. Two methods suggested in a Microsoft Answers post and in a TenForums post worked for me.

Method 1.

1. Open the "Device Manager" from the Control Panel or the Settings menu, disabled and then re-enabled "AC Adapter" and "ACPI Compliant Control Method Battery".

Method 2.

1. Run the Group Policy Editors gpedit.msc as Administrator 
2. Navigate to expand "User Configuration", "Administrative Templates", and then "Start Menu and Taskbar", locate "Remove the battery meter", choose "Disable". 
3. Restart the computer.

Fixing Problem that Windows Mail App Account Settings Are Out of Date

I use Windows Mail app to access my Hotmail email account. It suddenly started complaining about "Account settings are out of date". The Mail app would ask you to "Fix" it, guide you to "Update" account information. It appears that the "fixing" process is successful. However, it does not fix the problem. It does not appear to even fix the problem when I delete the account and add it back in. Eventually I find out that I need to choose the right option other than the email type option list superficially seems to suggest when I add the account back in. Below are the steps.

1. Click on the "Settings" button on bottom of the left pane
2. Click on "Manage Account" from the "Settings" menu
3. Click on "Add Account" from the "Manage Account" menu
4. Select "Exchange, Office 365". Note that on the face value, the first option, "Outlook.com, live.com, Hotmail, MSN" seems to be the choice we should choose, after all the email account in question is a Hotmail account. In fact, for many users, the first option is not the right option because Microsoft  has gradually migrate Hotmail accounts to "Office 365". 
5. Enter a Hotmail address and password

Converting SVG to PDF on Linux Command Line

A number of tools available for converting a SVG to a PDF file on Linux command line, for instances,

• rsvg-convert
  

  
         $ sudo apt-get install librsvg2-bin
         $ rsvg-convert -f pdf -o mygraph.pdf mygraph.svg
      

• ImageMagick
  

  
         $ sudo apt-get install imagemagick
         $ convert mygraph.svg mygraph.pdf
      

• Inkscape
  

  
         $ sudo apt-get install inkscape
         $ inkscape mygraph.svg --export-pdf=mygraph.pdf
      

A few others include GhostPDL and CairoSVG. Each of these tools has its own limitations, particularly, supported SVG features. My limited use points to that Inkspace appears to have the most supported features.

Websites for Testing Regular Expressions

Below is a list of websites that I use to test regular expressions.

• regex101.com
  • Support: PHP, Python, Javascript, Golang
• regexplanet.com
  • Support: Java

Visualizing and Learning Programming, Data Structures and Algorithms.

This post bookmarks resources for visualizing and learning programming, data structures and algorithms.

• The CS Unplugged project
• The OpenDSA project
• The Runestone Interactive project.
  • Problem Solving with Algorithms and Data Structures using Python
• Python Tutor. Visualizing programs in a number of programming languages, such as, Python, Java, JavaScript, TypeScript, Ruby, C, and C++.

Web-based Intergrated Development Environments (IDEs)

A number of Web-based IDEs have been made available. Although they are not as sophisticated as desktop IDEs, such as Microsoft Visual Studio and Eclipse, they are quite convenient to share some code. This post serves as a bookmark for a few Web-based IDEs that I came across. 

• Cloud 9. You may sign up a free account; however, a credit information must be provided. It supports many popular languages.
• Repl.It. Free accounts are available. It also supports multiple programming languages. It is simpler and not as sophisticated as Cloud 9. 

Rendering Jupyter Notebooks (IPython Notebook) on Github Pages Sites

There are a number of solutions to render Jupyter notebooks on Github Pages sites.

• Convert Jupyter notebooks to static html pages using nbconvert. For example, we have a Jupyter notebook file, my_example.ipynb. We run nbconvert as follows,

  
    jupyter nbconvert --to html --template full 2017-02-01-112657.ipynb 

  
  The above produce a whole HTML document including HTML header. If you wish to embed the notebook into your own page, you may use option basic as follows,

  
    jupyter nbconvert --to html --template basic 2017-02-01-112657.ipynb 

• Another method is to use a Pelican extension, see ipynb_reader.
• You can also use Jupyter's nbviewer service. See the following example and examine the URL.
  
  Example using nbviewer

Note that Github can now render a Jupyter notebook from its repository view. However, that is different from viewing a Jupyter notebook on a Github Pages site.