DEV Community: Aaron Johnson

Introduction to Matplotlib

Aaron Johnson — Sat, 20 Apr 2024 13:48:49 +0000

What is Visualization?

Visualization is the ability to graphically represent data so that insights can be derived from the dataset, some of the insights that can be derived are the correlation between the various features, the count of distinct values for each feature, and if you're looking at a time series data (Data that changes with time, such as daily temperatures), visualization helps in seeing the general direction of the data. In python, there are various libraries that enable data visualization. Some of the most commonly used ones are Matplotlib and Seaborn.

For the purpose of demonstration, I will be using the House Rent Prediction Dataset from Kaggle. To install both the mentioned libraries, if you're using an online notebook such as Google Colab it should be pre-installed, else in your local terminal you can use the following commands if you already have python installed:



pip install matplotlib

Matplotlib

To import the Matplotlib library, the code below is used:



import matplotlib.pyplot as plt

From the code the import is used to following the following library to be imported. Now the next part is interesting, so we will generally use the pyplot component of matplotlib. pyplot essentially makes matplotlib act like matlab. Finally plt is a name we are giving to access the libary, so instead of using matplotlib.pyplot.etc we can just use plt.etc

The various graphs that are available in matplotlib are:

Line Charts
Bar Graphs
Pie Charts
Scatter Plots

We can also display images as well which will be covered at the end. It would also be helpful to note that matplotlib also supports 3D plots which won't be covered in this post.

After importing the House Rent Dataset, we can see that the various features of the dataset are: Posted On, BHK, Rent, Size, Floor, Area Type,Area Locality, City, Furnishing Status, Tenant Preferred, Bathroom, and Point of Contact

Line Charts

Line Graphs in very simple terms, show how data moves over time or the relationship between two features. To plot a line graph, you can call the function plt.plot(). Let us plot a Line Graph where the x axis is the size of the apartment and the y axis is the Rent as shown below:



plt.plot(df['Size'], df['Rent'])

However you can see that the line is all over the place.

This is where we sort both the features, using one as reference. In this case, we will sort both with respect to size.



zl = zip(df['Size'], df['Rent']) #combines lists into a tuple
sl = sorted(zl, key=lambda x: x[0]) #sort tuple based on first value
x,y= zip(sl) #Splits the values into x and y

Now we get a better graph.

Bar Graphs

Bar Graphs essentially show the numeric values of various categories, ie, the count for each category, the values associated with each category, etc. We will create a bar plot where the categorical values are the cities and the heights of each bar is based on the Rent. The code to create a bar graph is given below:



plt.bar(df['City'],df['Rent'])

Pie Charts

A Pie Chart is a circular representation of the total distribution of values of categories, ie, count of the categories. In this example, we will create a pie chart for the cities:



city_counts = df['City'].value_counts() # to get unique values and their counts
plt.pie(city_counts, labels=city_counts.index) #we use the unique values (cities) as the label
plt.show()

Scatter Plots

A Scatter Plot essentially helps in visualizing the relationship between two features. In this example, we will create a scatter plot in which the x-axis is the Size and y-axis is the Rent:



zl = zip(df['Size'], df['Rent']) #combines lists into a tuple
sl = sorted(zl, key=lambda x: x[0]) #sort tuple based on first value
x,y= zip(*sl) #Splits the values into x and y

plt.scatter(df['Size'],df['Rent'])

Finally, you can display images using the imgshow() function as shown below. To read an image we use the cv2 library which will be covered in another post.



import cv2 as cv

image = cv.imread("/kaggle/input/transformers transformers_cars-HD-2149224348.jpg") # Reads the image
plt.imshow(image) #displays the image

If you would like to go more in depth about matplotlib. Here are a few resources available:

If you have any inquiries, or want to point out any corrections or have any feedback in general, feel free to let me know!

Introduction to Git [Part 2]

Aaron Johnson — Wed, 28 Sep 2022 07:03:44 +0000

Disclaimer: I've re-arranged the commands with the 1'st part so as to have a flow with the introduction of commands.

Some Basic Git Commands

1) git status
2) git commit
3) git checkout
4) git push
5) git reset

1)git status - The command is used to display the state of the working directory and the staging area, it also shows which files have been tracked (Added to staging area) and untracked (Not Added to staging area).

2) git commit - The command is used to create a snapshot of all the changes made to the repository and will not be changed unless asked to and this will be "pushed" to the main repository. The syntax of the command is "git commit", if you would like to add a message to the commit, type the command as git commit -m "Enter message here", and if you use the command as is, it will open a message editor where you enter the message for the commit and exit that screen type ":wq".

So this is how it should appear after using the command.

example text
1 file changed, 1 insertion(+)
create mode 100644 text.txt

3) git checkout - The command is used to change between branches in the repository. In this example, I have created a new branch called "demo" using the "git branch branchname" command. So to change the branch, the syntax would be "git checkout branchname", in this case, it would be "git checkout demo" and the following should appear.

git checkout demo
A text.txt
Switched to branch 'demo'

4) git push - The command is used to push all the changes in your repository to the main repository. When you use the command


 push origin <branch_name>

The following should appear.

Enumerating objects: 5, done.
Counting objects: 100% (5/5), done.
Delta compression using up to 8 threads
Compressing objects: 100% (2/2), done.
Writing objects: 100% (3/3), 254 bytes | 254.00 KiB/s, done.
Total 3 (delta 1), reused 0 (delta 0), pack-reused 0
remote: Resolving deltas: 100% (1/1), completed with 1 local object.
To [The URL of your repository]

Note: When you're pushing to a remote repository make sure that the branch from which you're pushing from locally matches the same as the branch you're referring to in the push command, ie main to main or custom_branch to custom_branch.

5) git reset: The command resets your cloned repository or in better terms, undoes the changes you've made to the repository.

For example, I've added a file test4.c to the staging area by mistake and now I want to undo it. Currently, if i use the git status command I will see



On branch main
Your branch is up to date with 'origin/main'.

Changes to be committed:
  (use "git restore --staged <file>..." to unstage)
    new file:   test4.c

As clearly shown, the file is staged. To undo this, use the command git reset, and now when you use the git status command, you will see



On branch main
Your branch is up to date with 'origin/main'.

Untracked files:
  (use "git add <file>..." to include in what will be committed)
    test4.c

nothing added to commit but untracked files present (use "git add" to track)

Now the file is untracked and your staging area is empty.

I hope the post was helpful and as usual, here are a few more sources to learn from.

A few sources to learn the command line

Linux
- Ubuntu
- TryHackMe
Windows
- Mozilla
If you fancy dual-booting your Windows laptop with Ubuntu
- LinuxTechie

Getting started with Machine Learning

Aaron Johnson — Wed, 29 Jun 2022 14:13:54 +0000

Machine Learning can feel a bit complex at times for beginners such as myself however it is not impossible to learn.

I've recently entered the field of Machine Learning and have created a few basic ML models, In the beginning, I had to search a lot for a few good sources to help me in my journey, so the purpose of this post is to hopefully be a one stop list of resources for beginners interested in the field.

Coding with Python

Python for beginners (University of Michigan) (paid)
codecademy (free/paid)
w3schools (free)

Machine Learning

Machine Learning (Stanford University) (free/ certification - paid)
towards data science (free)
codebasics (free)
geeksforgeeks (free)

As I go in-depth in the field, I will update (if necessary) this post, if you have any resources which you would like to see in this, feel free to mention them!

Before I end this, I would like to add something. I know it feels a bit overwhelming when you're hit with a ton of maths, libraries, and so on. It's very important to go at this at your own pace. Take as much time as you want, do not be hard on yourself, and if you have any issues with your code, you can always check out Stack Overflow and if you do not see your question there, you can always ask one.

Take your time, make sure you're understanding what you're doing, play around with datasets and have fun!

Happy Coding!

Introduction to Git [Part 1]

Aaron Johnson — Thu, 28 Oct 2021 03:48:53 +0000

What is Git?

Git is a free and Open Sourced Version Control System, ie, allows programmers to keep track of any changes with files involving collaborative software development.

Some Basic Git Commands

1) git init
2) git clone
3) git pull
4) git add

// I will be using VS Code for these examples.//

Before you can use Git in VS Code, you first need to clone a repository. Open Github and the repository that you want to clone, fork the repository. Once the forked Repository opens, copy the URL. Open VS Code and in the "Get Started" tab, under "Start" Click on "Clone Git Repository" and paste the URL of your forked Repository. After creating files for the repository click on View -> Terminal or shortcut: ^` for Mac.

1) 'git init' : This command is used to initialize a new local repository. To create one:

First, open your command line and navigate to the folder where you want to initialize it. If one does not exist you can create one using the mkdir folder_name command.
Now, initialize the folder using the command git init and the following should appear.

Initialized empty Git repository in /Users/user_name/Documents/test/.git/

2) git clone: This command is mostly used by users who want to clone the remote repository to their local system through the command line tool.

git clone as the name suggests clones a Github repository to a new location (on your local system in this example). The syntax for the same would be
git clone <url>
To clone a Github Repository:

First, go to the Repository's Github Site, then on the main page, Click on the Green Code button -> copy the HTTPS URL.
Now, on your command line navigate to the folder where you want to clone the repository, use the git clone command and the following should appear.

Cloning into 'test'... remote: Enumerating objects: 3, done. remote: Counting objects: 100% (3/3), done. remote: Total 3 (delta 0), reused 0 (delta 0), pack-reused 0 Receiving objects: 100% (3/3), done.

Now you successfully cloned the repository. I've created a test.c file in my test repository, so after cloning, if I use the ls command (MacOs), the name of the file shows, indicating I've cloned the repository and all its data.

3) git pull: The command fetches the data from the remote repository and updates your local repository.
After cloning, many files would've been added/removed/modified by other contributors.

If you want to contribute another file, it would be great if your cloned repository was updated to match with the remote repository, to avoid clashes and creating avoidable inconveniences.

This is why the git pull command is used. To pull from the main branch of the remote repository use the following command
git pull origin main

and this should be the output.

`
remote: Enumerating objects: 3, done.
remote: Counting objects: 100% (3/3), done.
remote: Compressing objects: 100% (2/2), done.
remote: Total 2 (delta 0), reused 0 (delta 0), pack-reused 0
Unpacking objects: 100% (2/2), 606 bytes | 151.00 KiB/s, done.
From https://github.com/AaronJohnson02/test

branch main -> FETCH_HEAD 0beb25d..703275f main -> origin/main Updating 0beb25d..703275f Fast-forward test2.c | 1 + 1 file changed, 1 insertion(+) create mode 100644 test2.c `

Now you've updated the cloned repository to match the remote. To verify this, if you reuse the command, you should see:

branch main -> FETCH_HEAD Already up to date. `

4) "git add" - The command is used to add files to the staging area and it's syntax is "git add filename.extention".

Let us take an example, where we have created a file called "text.txt". When you open the terminal in VS code type in "git add text.txt". To check if the file has been staged, use the "git status" command and the following should appear.

On branch main
Your branch is up to date with 'origin/main'.

Changes to be committed:
(use "git restore --staged ..." to unstage)
new file: text.txt

In the terminal untracked files will appear in red and tracked as green.

Here are a few sources for those who are interested in learning Git.

1) Atlassian - Version Control with Git (Paid)
2) Google - Introduction to Git and GitHub (Paid)
3) Atlassian (Website)
4) freecodecamp (Website)
5) geeksforgeeks (Website)

I hope this helps, I am too learning git and if you have any feedback on how I can improve or any changes to make, please feel free to reach out!

My experience with the Github Community

Aaron Johnson — Fri, 15 Oct 2021 17:17:57 +0000

Introduction

Hey, I'm a 1st-year Computer Science student and I know the absolute basics of Python, C++, C, and Java. I have also begun to learn git. I was introduced to Github through a YouTube recommended video. After watching the video I was intrigued and so I started to slowly expose myself to the Open Source World. As mentioned, as I know the bare basics of a few programming languages, the number of Repositories that I can contribute to is greatly reduced but I try to help repositories with Documentation till I reach a good level with my knowledge of programming languages.

Experience

Being a newbie to the Github community, I was absolutely lost, I had no idea what Repositories, Pull Requests, Issues, Forks, etc were. Since many companies use Github for many of their projects, there are formal rules, signing of documents and many strict guidelines to be followed when contributing to their Repositories and since I haven't been exposed to such scenarios before, you can believe there were a lot of mistakes on my behalf...and this is where the Owners of the repositories come in. I have been very fortunate to have contributed to repositories with the most patient, understanding, and amazing people ever, who have helped me with my mistakes irrespective of how many I made and I absolutely appreciate them.

Conclusion

My experience to date with the Github Community has been absolutely amazing and I hope it stays this way. I also believe the better you treat the contributors for your repository, the more that join and the bigger the community. This has been my experience so far, how has yours been?

Contributing using the Github website

Aaron Johnson — Wed, 19 May 2021 04:54:30 +0000

In this post , I will show you how to contribute to repositories on Github using the Github Website .

I’ve received the permission of Mashiya to use his repository for this post .

1) Finding a repository

Find a repository that you would like to contribute to using the Github Search bar . Now after opening the repository , you should see the given photo .

2) Fork the repository

On top right of the screen , you would see a fork button , click on that to fork your repository and then your webpage should look like this.

3) Adding a File

After forking the repository , you can add a file to your repository by clicking on “Add File” and then click on “Create new file” or “Upload file” . I’ve clicked on the former and the webpage should look like this . I’ve created a simple Hello World Program .

After typing your program scroll to the bottom of the screen to commit the change to your repository either on the main branch or to create a new branch for your commit . You can add a title and description to your commit if you want to .

Now move to the main repository page .

4) Creating a Pull Request for your changes

If you add commits to any branch other than the main branch , you should see a similar tab on the webpage .

If you do not see the given tab , on the tab of the repository click on Pull Request and then you should see this . Change your branch to the branch where you added the files .

Add a title and a description for your Pull Request and then click “Create Pull Request”.

You have now successfully contributed to a repository.

Hope this post helps you out and if you feel that I’ve missed anything or could’ve done something better feel free to let me know . I will soon do a post for contributing using Git .

My Favourite Podcasts

Aaron Johnson — Tue, 18 May 2021 06:15:16 +0000

Have you ever wanted to listen to a podcast but don’t know what to listen to ? Here’s a list of my favourite podcasts on Spotify .

1) Open Source Security Podcast

by Josh Bressers and Kurt Seifried

If you’re working or studying in the field of Open Source security or if you’re curious or even just want to stay up to date with tech related stuff this podcast is the one for you . The Podcast covers a range of topics and they have show notes for each of their podcasts so you can dive deeper in the topics that they cover . The duration of the podcast is varies from 29-40 mins.

2) Simplypodlogical

by Simply Nailogical

If you want to listen to a podcast covering various general topics . Simplypodlogical is the podcast for you . It covers various topics from colleges to relationships to cancel culture . The duration of the podcast varies from 40-90 mins .

3) Think Fast , Talk Smart Podcast

by Stanford GSD

If you want to better your communication skills , this podcast is for you . Each podcast covers various skills such as how to write effectively , how to communicate during a time of crisis , etc . Definitely would suggest listening to this podcast .

4) TED Talks Daily

by TED

TED Talks Daily is an audio version of TED talks . Podcast Episodes are uploaded very frequently and each speaker covers a different topic . So if you want to learn new things without needing to look at a screen for a long time , this is the podcast for you .

So this is my list of favourite podcasts , hope you begin to have a liking to one of them . What are some of your favourite podcasts ?

Tech Favs

Aaron Johnson — Tue, 11 May 2021 13:31:15 +0000

So a friend and I were having a conversation of various services and products offered by Tech companies like Google . So a thought came to me that many people like some companies over others . So a question to you reader , which is your favourite tech company and which isn’t and why do you like/dislike that/those companies and what do you think they should do to improve ?

Self-Care During the Pandemic

Aaron Johnson — Mon, 19 Apr 2021 11:37:35 +0000

INTRO

The Coivd-19 Pandemic has not been great for many people both physically and mentally (myself included). I am optimistic about the situation and I hope things get better. I know for a fact that people may be more hygienic after this. Many countries and states have declared new curfews and lockdowns due to the increase in cases. So I have created this as a way of trying to help you take care of yourself during the lockdown.

STAY AWAY FROM NEGATIVE NEWS

I understand that the news is important but I would suggest that you don’t pay attention to the news but if you do want to, see your local news and updates of the covid situation in your area. If you want to read the news, preferably read the news of the fields you are interested in, ex: Technology, Astrology, etc preferably topics that do not contain negative content or watch some stand-up content or comedy movies. The reason I made this point is that exposing yourself to negative news will subconsciously start to slowly affect your mental health, it may not be an instant effect, it will be after a while.

DO THE THINGS THAT YOU LIKE

If you’re a busy student or a professional, you should always keep at least 30 mins a day to do something you love, may that be, reading a book, watching standup, playing an instrument, playing games, etc. I felt that doing something I love for 30 mins a day made me feel better and more energetic and made it much easier to do the work I have for the day.

CHANGE YOUR ROUTINE

If you feel that your days are just repetitive, change it up a bit, maybe wake up a bit earlier than you used to, or do meditation just after you wake up, etc. I felt that changing my routines helps differentiate each day even if it’s by these small acts. It may not seem like a great thing to change but it will be a difference even if it’s decorating your room. See what suits you, try things out. Try out new skills too, if that’s drawing, singing, playing an instrument, designing, etc, you may discover new things about yourself.

TALK TO PEOPLE

Being home alone isn’t fun but it doesn’t mean, you’re alone, thanks to the people providing us with internet and cell services, we can talk to people even if it’s for 30 mins, a short conversation a day will make a lot of difference. Another way of contacting people across the world without providing any personal information about yourself are apps like Discord ( available on App Store and the Play Store) and Slowly ( available App store and the Play Store ), etc which allows you to connect to other people and you may make new friends. ( To discover Discord servers you can search here and type the type of server you’re looking for, ex: studying, debating, gaming, etc and then choose the server you want to join ) , (Slowly is an online mail messaging app where you write ‘letters’ to users and the time it takes your letter to reach your user depends on their geographical location so the time of arrival of messages varies from 30mins to 26hrs for me at the moment).

SLEEP

I cannot stress enough how Sleep is very important. You should have at least 8hrs of sleep and if you have to have less than it due to work, etc, have a compulsory 30mins or two 15min rest during your day. Sleep helps to rejuvenate your energy and helps to clear your mind.

TALK WITH PROFESSIONALS

If you ever feel depressed or very anxious, talk with your friends but always if you feel the need to, talk to a counselor or call your local helplines in the end counselors are trained people who do know how to help you and they will never tell anybody the content of your conversations and you can also tell them to not tell anybody that you’re visiting them (if you feel the need to ) and trust me talking to professionals will help you out. You don’t have to only message them if you’re depressed or anxious, you can talk with them even if it’s for the small things like, having a bad day or don’t know why you’re lethargic or just want to vent out, etc. Never hold your emotions inside find an outlet for it, even if that’s converting your emotions into poems or stories. I, unfortunately, found out the hard way but I am ok now.

So these are the ways that have helped me bear the lockdowns and I hope someway it does for you too and if you have any suggestions feel free to let me know. This is a difficult time, I know that, and remember, you’re never alone. Take care of yourself.

How to make learning to code easier and fun

Aaron Johnson — Sun, 18 Apr 2021 18:29:45 +0000

//Before I begin , I would like to say that these
//methods helped me out , so it might not necessarily
//mean that it works for you , so with that , here are
//the methods that helped make learning to code easier.

1. Don’t be hard on yourself

Primarily , Don’t be hard on yourself , there will be some days when things might not go great or you feel defeated . It’s ok , take a day off and always have enough sleep. There’s always tomorrow . I know it might not be the best of advice but taking it a bit easy helps your performance (at least it did for me). I feel that if one is hard on themself , it makes the thing that they are trying to do very tedious. So please do take it easy , when I mean easy , I don’t mean to not do anything and be extremely carefree , what I mean is when you’re learning and things don’t go well don’t become upset or anxious , take a deep breath and do something you love and then get back to it and if it still doesn’t go well , there’s always tomorrow.

2. Have a partner for your journey .

Doing things by yourself isn’t necessarily a fun thing to do . Find someone to join you in your journey , maybe a friend or classmate , working with people helps you learn quicker and you understand things more easily and if anyone is stuck somewhere , y’all can help/learn together.

3. Use available websites to program together

If you’re unable to meet together or want to code on your individual systems , there are websites that allow you to share code and to edit one another’s code in real time . A platform I use to share or contribute my code to repositories , I use Github and if I want to code in real time where we can see each other type and edit one another’s code , I personally use Replit as it helps you to learn together while helping one another out by correcting one another’s mistakes.

4. Create or Contribute to Repositories on Github

Creating/Contributing to Repositories have helped me apply my knowledge to required Program requests . There are hundreds and thousands of Repositories on Github , from base level of coding for each language to Applications by Big Companies like Google and Microsoft . If you’re new to programming , search for a repository for the language you’re learning and you’ll find many and some that are for new programmers and there are some with a list of desired programs the Repository Owner wants to add to his/her repository , y’all can use this as a way of seeing your progress and a feeling of accomplishment and a confirmation that you understand what you’re learning .

5. Change up your work/studying environment

If you prefer learning by yourself and feel lethargic or unmotivated , change up your environment , clean up the workspace and if listening to music/podcast helps you , go for it , preferably relaxing or chill music but see what fits you.

So yeah , these are my methods on how to make programming easier and fun and if you find that I went wrong somewhere or if you have another method to add , feel free to let me know.

Dogecoin

Aaron Johnson — Sun, 18 Apr 2021 14:45:46 +0000

What is Dodgecoin and who created it ?

Dogecoin is a cryptocurrency invented by Billy Markus and Jackson Palmer . It wasn’t designed to be used as a form of payment but as a mere joke .

What is Doge ?

Doge is a meme which portrays a Shiba Inu dog alongside nonsensical phrases in multicolored, Comic Sans-font text.

Why has the Dogecoin become popular ?

The coin has many influential celebrity supporters such as Carole Baskin , Gene Simmons , Kai Greene , Mia Khalifa , Snoop Dogg , Lil Yachty and the most notable , Elon Musk .

Elon Musk came in contact with the coin back in 2018 and used to meme about the coin on his Twitter account . Due to this more and more people were directed to the coin which helped boost the coins price by even 800% , the percentages seemed to increase every time Elon Musk talks/memes on the coin . ELon’s ability to dramatically influence the crypto market through social media posts became known as the “Elon effect.”

In short, it seems the selfless community, the light-hearted origin of the project and the real-world utility were the biggest contributors to dogecoin’s early success in the crypto market. Over the last few years, however, dogecoin has really become a kind of cryptocurrency avatar for meme culture, fueled by online communities and support from internet personalities like Elon Musk. As that culture has risen in influence, DOGE has risen in value – essentially taking on a life of its own that its creators never intended.

Why my posts are the way they are .

Aaron Johnson — Sat, 17 Apr 2021 16:39:16 +0000

Background Information about me :

So if y’all were wondering , I am a grade 12 student who’s interested in programming . I find ML and Cybersecurity interesting and am hoping to get into these fields after college . I love talking about things I find interesting and I also like the concept of open source .

About my posts :

As a student who’s new to programming , I know for a fact that I am not qualified to teach others as I do not have enough knowledge to teach . So this brings me to the topic of my posts . As mentioned above , I love talking about things I find interesting , if you have seen any of my other posts , I’ve spoken about Pi network , general advice , ubuntu and a bit about open source . Though this may not help anyone in particular , I find it interesting so I want to share it to people . I’ve had over 800 views on my posts till date and I have 3 reactions per post . I know it may be that reactions isn’t proportional to the amount of people who find it interesting but as a student I’ve always had the thing that the more the reactions , the more people who liked it .

So what I want to say is that , if you’re new here and you don’t get enough reactions , don’t let that get to you , if you like something , share it , talk about the things you like . You do You .

If you’ve reached out so far , thank you . Hope you’re doing good and I hope this post makes sense , do not know whether or not to make this a temporary post but if you’re new person , keep sharing things you find interesting don’t hold back . As long as you’re happy that’s all that matters . Cheers