TU Numerical Library

This library exists mainly for TUACM students to get a working project under their belt to help bridge the gap between theory and practice, so if you need performance critical code, you're probably better off using another library.

Setting Up

Set up a github account.
Fork this repository.
There are some differences between Windows and Mac/Linux, so the next step will cover both cases. Everything will be done in the terminal.
- On Windows, open the Ubuntu or Debian App (probably Ubuntu) and run the commands
```
	joseph@computer:tunl$ ln -s /mnt/c/Users/[user] ~/win-home
	joseph@computer:tunl$ mkdir -p ~/win-home/dev/
	joseph@computer:tunl$ cd ~/win-home/dev/
```
  where [user] is your username on your Windows computer. We're just creating a directory where you can put your projects that should be easy to access from both your terminal and on Windows.
- On Linux/Mac, open the Terminal or Terminal Emulator and run the commands
```
	joseph@computer:tunl$ mkdir -p ~/dev/
	joseph@computer:tunl$ cd ~/dev/
```
Then type the following command on Windows, MacOS, or Linux.
```
	joseph@computer:tunl$ git clone https://github.com/[github username]/tunl.git
```
For example, I would type
```
	joseph@computer:tunl$ git clone https://github.com/TheLandfill/tunl.git
```
since my username is TheLandfill and someone with the username password would type
```
	joseph@computer:tunl$ git clone https://github.com/password/tunl.git
```
Follow the instructions on setting up for C/C++ development. If you're on Windows and you followed the above steps, you can use the ~/win-home/dev/ path instead of the /mnt/c/Users/[user]/dev/ path proposed in the article as they're the same. You pretty much just need to install a text editor. If you already have an IDE that you like, it will work. If not, then just install Visual Studio Code for now and use that as your IDE.

Run the following command so that you can stay up to date with the main repository:

	joseph@computer:tunl$ git remote add upstream https://github.com/TheLandfill/tunl.git

You should only ever need to use the upstream master branch, which you can get using

	joseph@computer:tunl$ git checkout master
	joseph@computer:tunl$ git pull upstream master

You should now have downloaded the project and are ready to work on it. If you're on Windows, you'll find the project files in the directory C:\Users[user]\dev\tunl\ on Windows and you'll find them in ~/win-home/dev/tunl/ in the Terminal App (probably Ubuntu). If you're on Mac or Linux, then they'll be in ~/dev/tunl, a.k.a. /home/[user]/dev/tunl.

Contributing to the Repository

We're going to follow the git flow model, which consists of

Make a new branch for the feature you're working on. For example, let's say you want to implement the Matrix class. In which case, you would create a branch called matrix and switch to it using:
```
	joseph@computer:tunl$ git checkout -b matrix
```

Make the necessary additions, changes, and deletions to the files/code. Make sure to make a commit whenever you make a change that you would hate to have to reimplement if you delete it. Your commit messages should be descriptive enough for me to tell what you did. If you made a bunch of changes in a commit, create a file (call it commit-file.txt and put it in the dev/tunl/ directory) and write out the commit message in the format:

	One-Line Summary

	1.	First change is going to be a long line so that I can show you how
		to write multiline descriptions
	2.	Second change
	3.	Third change
	...

Making a commit consists of running git add [files you want to add], then running git commit -m "Some message describing what you did if it was a minor change" or git commit -F commit-file.txt with the format above. For example, let's say I add header guards to matrix.h and that's the only change I made. In that case, I would run the following commands:

	joseph@computer:tunl$ git status
	On branch matrix
	Your branch is up to date with 'origin/matrix'.

	Changes not staged for commit:
	(use "git add <file>..." to update what will be committed)
	(use "git restore <file>..." to discard changes in working directory)
		modified:   includes/matrix.h

	no changes added to commit (use "git add" and/or "git commit -a")
	joseph@computer:tunl$ git add includes/matrix.h
	joseph@computer:tunl$ git status
	On branch matrix
	Your branch is up to date with 'origin/master'.

	Changes to be committed:
	(use "git restore --staged <file>..." to unstage)
		modified:   includes/matrix.h
	joseph@computer:tunl$ git commit -m "Added header guards to includes/matrix.h"
	[matrix a1d6c56] Added header guards to includes/matrix.h
	 1 file changed, 3 insertions(+)

If, instead, I made a bunch of changes, I would edit the file tunl/commit-file.txt using the above format and replace the git commit command above with

	joseph@computer:tunl$ git commit -F commit-file.txt

Every so often, run the commands (I'm assuming you're on the branch matrix. If not, replace matrix with the name of the branch.)
```
	joseph@computer:tunl$ git checkout master
	joseph@computer:tunl$ git pull upstream master
	joseph@computer:tunl$ git checkout matrix
	joseph@computer:tunl$ git merge master
```
to make sure you're as up to date as possible. You don't want to be twenty commits behind and have to incorporate a bunch of changes into your branch all at once. If all goes well, we won't get any merge conflicts and we can move onto the next step. If, however, we do get merge conflicts, then we'll have to fix them by editing the relevant files, as shown in this article.
Once you've finished the feature and want to add it into the main repository (I'm assuming you're on the branch matrix. If not, replace matrix with the name of the branch.):
1. First, run the commands:
```
	joseph@computer:tunl$ git checkout master
	joseph@computer:tunl$ git pull upstream master
	joseph@computer:tunl$ git checkout matrix
	joseph@computer:tunl$ git merge master
```
Note that merging master with your current branch was a recommendation in the previous step, but merging master with your current branch is required at this point. You must successfully merge master into your branch before a pull request will be accepted.
Compile everything and run the tests to make sure everything is working.
Send a pull request from your fork.
We'll discuss what the changes you made did well and what needs to be fixed.

Fix anything that needs to be fixed while continuing to keep your branch up to date with master by running the commands

	joseph@computer:tunl$ git checkout master
	joseph@computer:tunl$ git pull upstream master
	joseph@computer:tunl$ git checkout matrix
	joseph@computer:tunl$ git merge master

and taking care of any merge conflicts.

Compile everything and run the tests to make sure everything is working.
Once everything is fixed, we'll merge it into master and you start working on a new feature.

Contributing Rules

You can ask anyone else for help at any point in order to follow these guidelines. If you break the rules, we won't merge your code into the main repository.

Give variables, files, functions, etc. a descriptive name. Doing so will make the code easy to read and understand, which means less time spent trying to figure out what you meant.
- One letter names and abbreviations are only acceptable if they're common. For example, num as an abbreviation for "number" is fine, i, j, and k are fine for iteration variables in a loop, x, y, and z are fine if you're talking about Cartesian coordinates, etc.
- Context can also help you shorten the length of variable or function names. For example, num_elements is a descriptive name, but if you're implementing a mathematical formula, you can just use n.
- Do not give the variables long names unless you cannot make the name any shorter.
- In short, if I can't tell what a thing is just by looking at its name, you will need to change it.
If you get warnings or errors when you compile the program, fix them.
To keep a consistent coding style:
- All constants will be uppercase and in snake case (e.g. TWO_THIRDS).
- All variables and function names will be lowercase and in snake case (e.g. distance_from_sun, area_of_circle).
- All classes and structs will be capitalized and in snake case (e.g. Simpson_Points).
- Camel case (e.g. areaOfCircle) is banned.
Keep comments to the bare minimum. Your code should be self-documenting, meaning I should be able to read it and understand what's going on without comments.