Coding with Vim & Using GitHub for Version Control

1. Vim:
The Vim text editor we use in Windows is a clone of the Vi text editor program for Unix/Linux. It is a defualt text editor for many developing environment.
There are quite a few commands, plug-ins for Vim and GitHub. We will just cover the fundamental ones to get you started. You colleagues in the industry (if you get an internship) are likely using Vim for programming and using GitHub for version control. It's good to know this.

Installation:

The official website for Vim is here:
https://www.vim.org/download.php

If you use your person PC in the class, just go ahead to download it. If you are using the desktop in a public environment and you don't have the admin access to install software to the computer, you can also use the portable Vim here. Extract the zip file under C:\Users\YOUR_USER_NAME\.......

You can find the executable file in the extracted folder. Just double click the 'GVimPortable.exe' to start Vim:



Use Vim as the text editor:
(from now on, please try to use Vim to write your code).

Vim often used commands: I showed you the ones I'm using all the time. Remember these ones, you will be good for now. You may find more commands here.

1.1 Basic Vim Commands
The most simple commands allow you to open and close documents as well as saving them. As with most other text editors, there are protections in place to help you avoid exiting the editor without having saved what you’re working on.

:e [file] - Opens a file, where [file] is the name of the file you want opened

:w - Saves the file you are working on

:w [filename] - Allows you to save your file with the name you’ve defined

:wq - Save your file and close Vim

:q! - Quit without first saving the file you were working on

:! python % - run the current script using Python

:set number - label the lines with numbers

:norm i# - comment line/lines

:norm x - uncomment line/lines

:new filename.py - create a new .py file in the same directory. The new file will be opened below the current edit window

:vert new filename.py - create a new .py file in the same directory. The new file will be opened beside the current edit window

:set guifont=* - set the font style and font size

1.2 Vim Commands for Movement
When using movement commands, you can put a number in front of them to make Vim complete a command multiple times. For example, 5h will move your cursor five spaces to the left, and 90j will put your cursor at the beginning of the 90th line down from where your cursor currently is.

h - Moves the cursor to the left

l - Moves the cursor to the right

j - Moves the cursor down one line

k - Moves the cursor up one line

H - Puts the cursor at the top of the screen

M - Puts the cursor in the middle of the screen

L - Puts the cursor at the bottom of the screen

w - Puts the cursor at the start of the next word

b - Puts the cursor at the start of the previous word

e - Puts the cursor at the end of a word

0 (zero) - Places the cursor at the beginning of a line (start a new line above)

$ - Places the cursor at the end of a line

) - Takes you to the start of the next sentence

( - Takes you to the start of the previous sentence

} - Takes you to the start of the next paragraph or block of text

{ - Takes you to the start of the previous paragraph or block of text

Ctrl+f - Takes you one page forward

Ctrl+b - Takes you one page back

Ctrl+ww - switch cursor among different vim windows

gg - Places the cursor at the start of the file

G - Places the cursor at the end of the file

# - Where # is the number of a line, this command takes you to the line specified

1.3 Vim Commands For Editing
Those who use Vim tend to use the term “yank” where most people would use the terms copy and paste. Therefore, the command for copying a word is yw, which stands for yank word, and the command for pasting whatever has been copied is p, meaning put. If you look up additional commands in the future, it can be confusing if you don’t know what yank and put mean when using Vim.

As with movement commands, putting a number in front of the command can increase the number of times a task is completed. For instance, putting a number in front of yy will increase the number of lines copied, so 5yy will copy five lines.

i - insert in front of the cursor

a - instert after the cursor

I - insert at the beginning of the line

A - insert at the end of the line

o (ou, not zero) - start a new line below

O (ou, not zero) - start a new line above

yy - Copies a line

yw - Copies a word

y$ - Copies from where your cursor is to the end of a line

v - Highlight one character at a time using arrow buttons or the h, k, j, l buttons

V - Highlights one line, and movement keys can allow you to highlight additional lines

p - Paste whatever has been copied to the unnamed register

d - Deletes highlighted text

dd - Deletes a line of text

dw - Deletes a word

D - Deletes everything from where your cursor is to the end of the line

d0 - Deletes everything from where your cursor is to the beginning of the line

dgg - Deletes everything from where your cursor is to the beginning of the file

dG - Deletes everything from where your cursor is to the end of the file

x - Deletes a single character

u - Undo the last operation; u# allows you to undo multiple actions

Ctrl+r - Redo the last undo

. - Repeats the last action

r - replace the current letter to something else. Just type the updated letter after you type 'r'

1.4 Vim Commands for Searching Text
Like many other text editors, Vim allows you to search your text and find and replace text within your document. If you opt to replace multiple instances of the same keyword or phrase, you can set Vim up to require or not require you to confirm each replacement depending on how you put in the command.

/[keyword] - Searches for text in the document where keyword is whatever keyword, phrase or string of characters you’re looking for

?[keyword] - Searches previous text for your keyword, phrase or character string

n - Searches your text again in whatever direction your last search was

N - Searches your text again in the opposite direction

:%s/[pattern]/[replacement]/g - This replaces all occurrences of a pattern without confirming each one

:%s/[pattern]/[replacement]/gc - Replaces all occurrences of a pattern and confirms each one

1.5 Vim Commands For Working With Multiple Files
You can also edit more than one text file at a time. Vim gives you the ability to either split your screen to show more than one file at a time or you can switch back and forth between documents. As with other functions, commands make going between documents or buffers, as they’re referred to with Vim, as simple as a few keystrokes.

:bn - Switch to next buffer

:bp - Switch to previous buffer

:bd - Close a buffer

:sp [filename] - Opens a new file and splits your screen horizontally to show more than one buffer

:vsp [filename] - Opens a new file and splits your screen vertically to show more than one buffer

:ls - Lists all open buffers

ctrl+ws - Split windows vertically

ctrl+wv - Split windows horizontally

ctrl+ww - Switch between windows

ctrl+wq - Quit a window

Ctrl+wh - Moves your cursor to the window to the left

Ctrl+wl - Moves your cursor to the window to the right

Ctrl+wj - Moves your cursor to the window below the one you’re in

Ctrl+wk - Moves your cursor to the window above the one you’re in

1.6 Marking Text (Visual Mode)
Visual mode allows you to select a block of text in Vim. Once a block of text is selected you can use visual commands to perform actions on the selected text such as deleting it, copying it, etc.

v - starts visual mode, you can then select a range of text, and run a command V - starts linewise visual mode (selects entire lines) Ctrl + v - starts visual block mode (selects columns) ab - a block with () aB - a block with {} ib - inner block with () iB - inner block with {} aw - mark a word Esc - exit visual mode

Once you’ve selected a particular range of text, you can then run a command on that text such as the following:

d - delete marked text y - yank (copy) marked text > - shift text right < - shift text left ~ - swap case (upper or lower)

Simple Vim Workflow Example
If you haven’t had a chance to play around with Vim much yet, you might be wondering what a simple workflow looks like when using it. It’s relatively simple:

Open a new or existing file with vim filename
Type i to switch into insert mode so that you can start editing the file
Enter or modify the text with your file
Once you’re done, press the escape key Esc to get out of insert mode and back to command mode
Type :wq to save and exit your file
Of course, there is so much more you can do with Vim, however as a beginner, the above steps are what a simple Vim workflow looks like.

2. Windows Command Line

dir - list the files in the current directory

cd .. - go back to the upper directory

cd C:\Users\..... - enter into a specific directory

copy fileToBeCopied.py fileToBeCreated.py - duplicate a file in the directory



del fileToBedeleted.py - delete a file in the directory

When install 'vim', check the box '.bat' to have vim included into the path environment variable. This will enable 'vim' command in the command line window.



To exit the vim mode, just type ':exit'.

3. Git

Git is a distributed version-control system for tracking changes in source code during software development. It is designed for coordinating work among programmers, but it can be used to track changes in any set of files. Its goals include speed, data integrity, and support for distributed, non-linear workflows. Git was created by Linus Torvalds in 2005 for development of the Linux kernel, with other kernel developers contributing to its initial development. Its current maintainer since 2005 is Junio Hamano.

If you are using your personal PC (Windows), download it from www.git-scm.com. If you use the lab computer, you can use the portable version of git here.
Enter the following directory and double click 'bash.exe'.



Now, find a git server to upload your code:
There are a few git service providers:



We will use GitHub for now. In the future, if you find BitBucket is better for your privacy it should be easy to change.

First, go to github.com to register an account using your permanent none-FLC email (so you can keep using it after you graduate).

Create a new repository:



Give a name to your new repository:



Click the 'Clone or download' button and copy the link in the window.



Type 'git clone http://.........' (copy and paste the link) in the command line window. Before you do this, make sure you are at the directory you want to use. I just use Desktop here:



Press 'Enter', the repository will be downloaded to the designated folder as a new folder.



Keep the .git folder there. The .git folder keeps the folder a Git folder but nothing else. Create a new '.py' file in this folder.

1. You can find gVim from your start menu and type ':new plotFile.py' to create a new file.
2. Or you can Right Click an empty '.py' file and create it using Vim.

Type the following simple plotting python code in Vim. When you are done, save the changes first using ':w' + Enter, then type '! python %' + Enter to run the code: (% represents the current script so you don't have to type the name of the current file)



You can add Line Numebers (':set number') and change the font size (':set guifont=*'):





Type ':wq' to save and quit the current file. Go back to the command line window. Enter the repository folder:



Type 'dir' to show all the files in the folder:



By looking at what you have in the folder (temperary local repository), you know which one you want to upload to GitHub:

The 'git add ....' command will add the 'to be submitted' file to a temperary buffer in your local drive. So nothing is submitted yet.



Next, type git commit -m "A new matplot py script":



Last, git push:



Go back to the GitHub, sign in with your account and go to your repositories. You can see the updated repository is already there (with the message you put in 'git commmit -m').



The above tutorial just covers the fundamental 'clone' and 'push' operations. There are many more operations like 'pull', 'merge' and others. After you know how to do the operations above, it must be very simple to learn others.