Everyone has different coding styles. Whether you are a clean or messy coder, it is fine as long as the program runs, right? Well, not quite. This quick article serves as a summary of what I’ve observed and learned, from coursework and working with people of various background (engineering, CS, biomedical, neuroscience folks…) throughout the years. To me, writing code is similar to writing an article. There are certain elements that can make a a piece of code good. What are some tricks and tips that might benefit YOU?

P.S. People write books on how to write nice code. It is not my intention to condense their work. This article is my own short summary that might most benefit beginner coders.

## Quality of code

Why do we bother to write quality codes? Code is meant for human to read, machine to execute. That means not only we want it to do a good job, we also want it to be presentable for other people to read and use. Nicer it is, more likely will someone use it in the future. I once need to film a video of me explaining my code as per request by my colleague who will be using my code for his project. It is in fact unnecessary if your code is self-explanatory.

So what is a good piece of code? Here are some criteria I believe are crucial:

• It runs - that’s just a bottom line to be correct and bug free
• It’s time-efficient - producing equal quality work that runs 10$\times$ faster than your friend
• It’s space-efficient - saving a 10-dim matrix you won’t use later to your memory space is completely unnecessary; reduce, reuse, and recycle (wait what?)
• It’s amenable - it’s easy to change value of some parameters or reuse your code for other projects
• It’s readable - the code is (1) simple and concise, (2) straightforward to understand what and why you’re trying to do, (3) systematics by using the consistent conventions

### So if I put a lot of #comments in my code, will it be more readable?

A short answer is: sure, but not necessarily. In a beginner coding class, it is common that either the teacher use a lot of # to describe what the line does, or worst, your perfectly runnable code doesn’t have enough # so your grader deducts some points and comments that it’s not “readable” enough. Comments serve a purpose to explain, hence making the code more comprehensible. Yet, a readable piece of code need not have a ton of comment. In fact, a good coder would always include a few commenting sentences only at the beginning of the code to explain the purpose, introduce key features, and describe input variables of the program, but not quite within the body of the code. Writing explanation for each line of the code can be redundant and definitely not elegant.

## General tips

Knowing what criteria contribute to a high quality piece of code. What are some good practice that every coder should bear in mind? In correspondence to the last section, I offer some tips that might be insightful for you.

• It runs - write down pseudocode; use debugging tools as much as you can; print values and sizes of parameters, number of iterations and results to screen; test ideas with smaller matrices
• It runs - employ defensive coding: a great way to ensure code correctness and prevent unforeseen bugs, typically used in computer security. A simple example of defensive coding is forcing an error message (or quitting the program) when the size of variable is not as instructed, even if this error is not detected by the compiler.
• Time-efficient - save your time writing your own function by using the built-in function that you can directly import and call.
• Time-efficient - avoid nest loops; the chance is you can probably find a smarter and better way to replace it.
• Time-, space-efficient - utilize lists, sets, and dictionaries appropriately and wisely. They are your friend.
• Amenable, readable - write in blocks: write separate functions instead of cramping everything in a never-ending __main__ body. It is clean and straightforward. View functions as LEGO bricks; they are building blocks one can build on top of the other to synthesize new material. You can reuse them to build various objects. What’s even better is that you need not modify the LEGO brick itself to build something new.
• Amenable - initialize hyperparameters that you might want to play around at the top of the program, name it appropriately and reuse it. If it’s fixed parameter, such as the number of samples or class, give it a simple variable name such as n, k and never use the actual value even if you know it.
• Readable - just like writing a book, an article, or a letter, we write in sections and paragraph to make the passage easy to read. Try using %% in MATLAB to section, or call self-defined functions in your python __main__ as if you’re reading the pseudocode.

## I’m a beginner coder, how do I advance fast?

You can only learn so much from an intro to programming class. After learning the concepts, it’s very important to put it in practice. Remember, there’s no overnight piano prodigies, so there’s no overnight coding genius. The most effective way to improve your code quality is to practice writing your own code on common problems. Unless you need to look up a certain function or to fix a bug, DO NOT search for answer or copy-paste from anyone. Once your code is up and running, compare it to solutions you find online. You will be surprise to see how much improvement can be done. Learn and absorb, write and repeat!

## Conclusion

It is a long way to go to master coding. A new fancy text editor doesn’t help as much as actual practice and implementation. If you are interesting to read more, there are plenty of coding guide just a quick search away. Good luck!