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Software Installation Instructions

For this course three software pieces are required:

   1. The programming language, Julia.

   2. A programming environment, Visual Studio Code, along with the proper extensions for the Julia programming language.

   3. The algorithmic design tool, Khepri.

This page contains the instructions for the required installations as well as some beginner tips on how to use either programming environment.

 

1. Installing the Julia programming language

 

First, install Julia: https://julialang.org/downloads/

More specifically, use: https://julialang-s3.julialang.org/bin/winnt/x64/1.8/julia-1.8.5-win64.exe

We recommend that you accept the default installation options.

 

2. Installing the Visual Studio Code Programming Environment

 

Second, install Visual Studio Code: https://code.visualstudio.com/

More specifically, use: https://code.visualstudio.com/Download#

Again, we recommend that you accept the default installation options.

Installing the Julia Extension

Third, launch Visual Studio Code and install the Julia extension.

In Visual Studio Code, click the View menu in the top bar, and choose Extensions (Ctrl+Shift+X).

In the extensions pane, type Julia into the search engine (on top) and select the Julia extension by clicking the install button. Visual Studio Code will install it. 

When the installation completes, restart Visual Studio Code.

 

Launching the Terminal and the Julia REPL

To run code, or to visualize the results of any program you run, you must launch the Terminal (or REPL).

If this tab is not already visible at the bottom of your workspace, go to the View menu in the top bar and choose Terminal (Ctrl+ç in a PT keyboard; Ctrl+` in a US keyboard).

The terminal, at the bottom of your screen, should indicate that you are running Julia. If you do not see a Julia prompt in your terminal (julia>), change the dropdown menu on the top right corner of the terminal to the Julia REPL option.

Another option to start the Julia REPL is available directly through the Command Pallete. Go to the View menu in the top bar and choose Command Pallete (Ctrl+Shift+P). Type Julia: Start REPL in the search engine that appears and select the corresponding option. The terminal should appear at the bottom of your workspace. The same can be achieved with the following key bindings: Alt+J Alt+O

3. Installing the Khepri algorithmic design tool

 

With the cursor in the REPL press Enter. Julia should have started and will begin its own installation process. When it's done, press the ] key. You will notice the Julia prompt (julia>) change to a package installation prompt (pkg>). In front of it, write:

add Khepri

When it's done, press backspace (<--) to return to the Julia prompt (julia>).

To test if the installation worked, write the following lines of code in the REPL and evaluate each one by clicking Enter after each instruction:

using Khepri

backend(autocad)

circle()

After AutoCAD starts, you should see an AutoCAD dialog asking if you want to load Khepri. Click on the button 'Always Load'. You should then see a circle in AutoCAD.

Note: in case the REPL shows errors and messages such as Please, close AutoCAD and retry or Please, start/restart AutoCAD just do what it says.

Beginner tips

 

Opening a Julia file

As you have seen, you can write and run programs directly in the Julia REPL. However, these instructions cannot be saved for later use. The REPL is useful for testing parts of your program and for visualizing the results of program runs. For more complex developments, you should work on a Julia file that can be saved to your computer.

To begin programming, open a new text file. Go to the File menu in the top bar and choose New File (Ctrl+N). This will open a new text file. You now have three options to convert it into a Julia file:

A.      Click on Select a Language and find Julia in the list (you may type in Julia to narrow down the search).

B.      On the bottom right corner of the workspace, you will notice the file is cataloged as Plain Text in the Select Language Mode button. Click on it to change the file type. A search engine will appear, where you should write and select Julia.

C.      Save the new text file with the Julia extension. Select the File menu in the top bar and choose Save As (Ctrl+Shift+S). In the Save as type dropdown menu select the Julia (*.jl) option, or simply add the extension yourself to the file name (e.g. Untitled.jl).

You can now start developing Julia code within the file.

 

Running Code

There are several options to run the code in your program. You may run the full program, or you may prefer to run only parts of it. In either case, the results of each run will show in the Julia REPL.

To run the full program click Alt+Enter when your cursor is anywhere within the program file. 

To run only parts of the file, you can use:

   Ctrl+Enter, which sends the current line (where your cursor is) or selection to the REPL.

   Shift+Enter, which runs the current instruction and moves your cursor downwards simultaneously.

Other useful commands include:

   Ctrl+D or Alt+J Alt+K for exiting the Julia REPL

   Ctrl+C to interrupt or cancel a process. Useful to break infinite loops or erroneous runs.

   Ctrl+L to clear terminal screen.

 

Inline visualization of results

We have shown you how to visualize program results in the REPL. There are other options for the visualization of results, namely inline visualization, which allows you to see the results of your program directly in the program file, in front of the line you just ran. Go to the File menu in the top bar, choose Preferences, and then Settings (Ctrl+,). Here open the Extensions drop-down menu and find Julia. In the Julia extension settings menu, change the default options in Execution: Result Type to inline or to both.

Troubleshooting

Julia REPL fails to start and an error message with either of the following texts appears: The terminal process failed to launch: Path to shell executable is not a file of a symlink or Path to shell executable does not exist.

If this is the case, Visual Studio Code could not find the Julia.exe file to launch the Julia shell in the editor. You must provide the path by hand.

Go to the File menu in the top bar, choose Preferences, and then Settings (Ctrl+,). Here open the Extensions drop-down menu and find Julia. In the Julia extension settings menu, find the Julia: Executable Path option. You will paste the correct path to the text box below. But first, find the file on your computer:

A.      The Julia.exe should be located deep in the AppData hidden folder. You will find this folder in your user folder (Users > *User Name*) if you check the Hiden items option on the View > Show/Hide tap. Alternatively, type %APPDATA% on the Windows File Explorer search engine and step back one folder. When in the AppData folder, open the following folders in sequence: AppData > Local > Programs > Julia > Julia-*.*.* > bin (*.*.* represents the Julia version you installed).

Copy this file path, all the way to the Julia.exe file, and paste it on Visual Studio Code. Add a second set of \ to each folder level. The final link should look something like C:\\Users\\*User Name*\\AppData\\Local\\Programs\\Julia\\Julia-*.*.*\\bin\\julia.exe

B.       If the file is not located in the AppData folder, as suggested, find Julia's shortcut either on your Desktop or Start Menu. Right-click on the icon and choose the option Open File Location. This will most likely lead you to another shortcut, so repeat the process until you reach the Julia.exe file. At this stage, follow the remaining steps in option A.

Mac users: run the following command on the REPL to acquire the bin file path on your computer.

println(Sys.BINDIR)