This is the ultimate step by step guide to installing Python, SQL, R and Bash and starting to learn coding for data science. It takes no more than 60 minutes and it’s 100% understandable for non-developers, too!

If you want to be a data scientist, a data analyst or just simply want to analyze the data of your business, sooner or later you will have to learn coding.

coding for data science languages python r sql bash
source: KDNuggets

There are 4 important languages that you should know:

  • SQL
  • Python
  • R
  • Bash (sometimes referred as “the command line”)

Here, on the Data36 blog, I provide many articles about coding for data science. However, as a foundation of every further conversation on this topic, you need to have Python, R, SQL and bash on your computer. Once you have them set up, you will be able to practice by yourself (and later build your own data projects too), as well as follow, practice and learn via my tutorial articles and videos.

In this article I’ll take you through getting these data tools step by step. At the end of the article you will have your own fully functioning data infrastructure with:

  • bash (and mcedit),
  • postgreSQL (and pgAdmin4),
  • Python 3 (and Jupyter) and
  • R (and RStudio)

Good news:

  1. I will show you the exact same tools that are used in real life data science projects.
  2. All these tools are completely free!

Yes, the funny thing is that most of the super-scientific stuff that you can read about in different data science articles are made using open-source data tools. How cool is that?

Anyway: first things first – let’s go and install Python, SQL, R and bash on your computer!

Note 1: The article was last updated on 30 October 2020.

Note 2: This article is more enjoyable if you do the steps and the coding part with me. If you are reading this on your mobile, I suggest saving the article for later (e.g. send it to yourself in e-mail) and coming back here when you have ~60 minutes and are on your Desktop computer or notebook.

Note 3: To have your data infrastructure correctly set up, you simply need to follow my instructions down here step by step — most of the time just copy-paste my code. So don’t be afraid to work on Terminal and writing code. It’s easy, even if you are not a programmer or data scientist (yet). The article is long, though, because I tried to explain each step as much as I could.

The Operating System

I use all my data tools (Python, R, SQL) on Ubuntu – which is a Linux operating system – and I suggest you do the same. My personal computer is a Mac, but you can have a PC too. In this case it doesn’t really matter, because we won’t install Ubuntu on our computer, but access it via the internet.

What we will do here is to connect to a remote server – type commands and make the remote server do the data analyses instead of our local computer.

coding for data science remote server simplified

(Note that you can set up Ubuntu on your personal/work computer too, if you really want to. But this is something we usually don’t do in real life, because with that solution we would limit our data processes to our computer’s capacity. Also we would lose some cool features.)

If you use a remote server for data analysis, you will be able to:

  • Access your data infrastructure from any computer with a login-name and a password (even if you lose or break your personal notebook). Don’t worry, nobody else will able to access your data on your remote server – it is completely private.
  • Automate your data scripts (e.g. make them run every 3 hours, even if you turn off your notebook).
  • Scale your computing power. You won’t be limited to your own computer’s capacity. Renting a few more processors or more memory is just one click away if you are using a remote server.
  • Use Ubuntu without installing it on your computer.

The only downside of going with a remote server is that it costs money. Fortunately these prices are very low (starting at $5 per month).

I’ve been creating all my coding for data science tutorials (videos and articles) using the exact same data stack that I’ll describe in this article. So if you want to follow me, it will be much easier for you if you go through this article step by step and set up everything like I do. To make everything work properly, please make sure that you don’t miss any of the steps and you do them in the same order as it’s written here! The most important parts of course are the code snippets. All the snippets are marked:

 like this

or

like this

Step 1: Get your remote server!

The next step is to find a hosting service to create your first remote server. I used many services and so far I’ve found DigitalOcean to be the best. You can rent here a server for $5/month (this will be perfect for us for now).

First, go to their website and create an account: DigitalOcean.com
Disclaimer: the link above is a special invitation link – if you use that, you’ll get $100 free credit for 60 days (and I’ll get $25 free credit). If you don’t want to use my link, you can simply click here instead. Note that in this case you won’t get the $100 credit.

You will land here:

coding for data science register to digital ocean

Register with your email address and you will get a confirmation email in your inbox. Confirm and you will see a screen where you can add your credit/debit card details or use PayPal. (For security reasons I always use PayPal.)

If you are done with that, you are just one step away from creating your first remote server. You will see the “Droplets” screen. Click “Create Droplet” (big green button, top right corner).

And you will end up here:

Make sure you are using these settings:

  1. “Choose an image:” Distributions: Ubuntu 18.04 x64data server on ubuntu 18 04
  2. “Choose a size:” Standard: $5/month
    This will be more than enough for now. If needed, you will be able to scale it up in the future. As you can see you’ll pay on hourly basis. This means that if you are using the server for 4 hours only, then delete it, you will pay $0.02. This is a very good deal.
    install python sql bash digital ocean choose a plan and a droplet size
  3. “Add block storage:” You don’t need this.
  4. “Choose a datacenter region:” Choose the one that is the closest to you. E.g. if you are in San Diego, choose San Francisco and if you are in India, choose Bangalore. I’ll choose Frankfurt as I’m in Stockholm at the moment.install python r sql bash digital ocean region
  5. “Select additional options:”  You don’t need this.
  6. “VPC Network”: Leave it as is.
  7. “Authentication:” One-time password.
    Here, you’ll have to create your own root password. You’ll see something like this:
    server setup passwordThe password requirement is pretty strict… Make sure you choose something that’s: At least 8 characters long — contains 1 uppercase (first and last characters don’t count) — contains 1 number — doesn’t end in a number or special character — as I said pretty strict.

    server setup new password
    Also, make sure you remember this password because you’ll need it soon!
  8. “Finalize and create:”
    “How many Droplets:”
     1
    “Choose a hostname:” You can use anything. I chose “data36-learn-data-science.”data coding digital ocean finalize
  9. “Add tags:”  You don’t need this.
  10. “Select project:” You don’t need this, either. (Go with the default.)
  11. “Add backups:” this is up to you – for my tutorials, you won’t need backups but on the long-term in real projects I recommend to use it. For now, you can just skip it.
  12. Click “Create.”
    Your server will be ready in ~60 secs.data coding digital ocean creating server

CONGRATS! You have your first remote server, where you can install Python, R, SQL and bash and then practice coding for data science.
(Note: you can destroy this server at any time by clicking “Destroy.”)

Step 2: Access your remote server!

It’s time to login to your freshly created remote data server.

You’ll need 2 pieces of important information for the login process.

  • The IP address of your droplet and
  • your root password.

The IP address can be found on the DigitalOcean website, where you have created your droplet. It’s right here:

ip address of digitalocean droplet old

Find yours on your DigitalOcean Droplets tab.

You’ll also need your root password… This is the one that you created when you have created your droplet.

server setup password

Depending on which operating system you use on your computer, you can access your server in different ways.

For Mac/Linux Users:

Open Terminal (on Mac I suggest downloading iTerm2  and using that instead of Terminal).

Type:

ssh [Username]@[IP Address]
  • [Username] is the username from the email, in this case: root
  • [IP Address] is the IP Address from the DigitalOcean droplet tab I showed you above.

In my case I will type:

ssh root@46.101.128.25

Hit enter and you are in…
(The next paragraph is important for Windows users only. You can skip it and scroll down to “Both Windows/Mac”!)

For Windows Users:

First download and install a program called PuTTy from here.

If you open Putty, you need to add the details (from the email) on this window:

data coding putty
  • Host Name (or IP address): the IP Address from the DigitalOcean droplet tab I showed you above (eg. 46.101.128.25 in my case)
  • Port: 22
  • Connection type: SSH

Click “Open” and you are in. It will ask for your:

  • username (“login as:”). Type: root
    (putting it simply, root is some sort of master user for your data server)
    Hit Enter…

Both Windows/Mac (oh and Linux of course):

Nice, you ssh-d (logged in) into your remote Ubuntu server. From this point, when you are on the terminal window, until you are disconnected to your remote server, you are going to be using Ubuntu 18.04. It also means that any changes you make here won’t affect your personal computer!

Let’s finalize things before we start setting up your data infrastructure!

If everything’s correct, the server asks some questions like:
Are you sure you want to continue connecting (yes/no)?
Type yes, hit enter.

Then it will ask for your password. Type the one that you provided when you have created your droplet, like 2 minutes ago… (Remember that I said that you’d need it soon?)

server setup password

IMPORTANT! If this is your first time on the command line, you might find it weird that the stars (*) don’t appear on the screen when you type your password, but this is how it is on Ubuntu. Even if you don’t see any characters typed in – don’t worry – it’s typed in!

data coding login to the data server

And done! You can start to install the data tools!

(Note: if you have so far used only graphical user interfaces (e.g. SPSS, Excel, Rapidminer, etc.), I know, this command line thingy could be intimidating. But believe me, once you’ve played around for 30 mins on this interface, you will find it fun! ;-))

Step 3: Install Bash!

Or wait… Great news! Bash is already set up, since it’s the built-in language of Ubuntu 18.04. (Again: sometimes it’s referred as “the command line.”)

I’ll get back to bash/command line in the next data coding tutorial articles and videos, but for now it’s enough if you know that you really need to care about learning this language because:

  1. You will use bash for every basic server operation – like moving files between folders, creating/deleting files, installing new programs (eg. Python, R or SQL, too), giving permissions to users, etc.
  2. It’s great for creating automations.
  3. It can be used as the “glue” between other data languages. (eg. moving something from SQL to Python, then from Python to R.)

For now, execute your first command: the “Hello, World!”

echo 'Hello, World!'

You will have Hello, World! printed on your screen.

data coding bash hello world

Don’t ask why we did that. This is a nice habit of programmers, so we did it too, but let’s move forward quickly and execute our second, more important command. We are going to create a new user:

adduser [newusername]

You can type anything for the [newusername] part. Whatever you put there, that will by your username. I’ll type dataguy. Like this:

adduser dataguy

If you hit enter, you will have some text on your terminal screen, then you need to add a new password for this user, some more text, then the name (your name preferably) and you can leave the rest empty.

data coding terminal create new user

You have just created a new user! Great!

This was needed for further steps: so far your username was root – and by default root user is not allowed to do a few important installation steps that we want to do.

Let’s execute one more command to give the right privileges to your new user:

usermod -aG sudo dataguy

(Obviously: don’t forget to replace dataguy with your new username)

From now on, we won’t use root user, we will use the new user you’ve created. So let’s logout from root user:

exit

This command will close the connection between your computer and your remote server. Log back in with your new username! Do everything as described in Step 2 above, but change root to your new username (in my case dataguy) and to your new password. As I’m on Mac I’ll type this – for instance:

ssh dataguy@46.101.128.25

Now you are logged in as a normal user.

And you can continue by setting up Python3.

Step 4: Install Python 3 and Jupyter!

Note: previously this article was written for Python 2 – but I have decided to upgrade it to Python 3. Python 2 won’t be supported after 2020. And Python 3 has been around since 2008. So if you are new to Python, it is definitely worth much more to learn the new Python 3 and not the old Python 2.

More great news! Python is already installed on Ubuntu 18.04 too! You can try the Python-way of “Hello, World!” very easily. Type into the command line:

python3

This will start Python. (While you are on Python, you can’t use Bash codes.)
Now type:

print('Hello, World!')
python3 hello world example

Notice that you get the same effect as it was with the echo command on bash. print and echo are pretty much the same, but print will work on Python and echo will work on Bash.

Anyway. Type:

exit()

This will stop Python and you will be back to Bash.

To use Python more efficiently in the future, you’ll need to install some add-ons.

The easiest way to install things in the command line is using the apt-get application’s install feature. You only have to type apt-get install, then the name of the add-on that you want to install. If the add-on exists, apt-get will find and install it. Unfortunately the version of apt-get on your server is not the most recent one, so as a first step, update it with this command:

sudo apt-get update

(Note: sudo is an additional keyword before your apt-get command that lets bash know that your user has the privileges to do installations.)

The command line will ask for your password! Remember: it is not necessarily the same as it was for your root user, but the one you set when you created the new user! Anytime it asks for your password, just type that one.

Now that you have the latest version of apt-get, give it a try and type:

sudo apt-get install mc

(If it asks whether to continue, just say yes.)

mc – that you have just installed – is a text editor for coding. We will use it soon.

Next 2 steps (one by one):

sudo apt-get -y install python3-pip
sudo apt-get -y install python3-dev

Again if it asks for your password, type it – if it’s asks if continue, say yes.
These commands installed pip and python-dev on your server, which will help you to download Python-specific packages.

Then type:

sudo -H pip3 install --upgrade pip

This command upgraded pip to the latest version.

Install Jupyter!

Let’s install Jupyter:

sudo -H pip3 install jupyter

You have installed one of the coolest Python packages: Jupyter. This is a tool that helps you to create easy-to-use notebooks from your Python code. Why is it so awesome? In my Python for Data Science tutorial articles and videos I tell more about it, but for now, let’s just configure and try it:

jupyter notebook --generate-config

This will create a config file for Jupyter on your server.

echo "c.NotebookApp.ip = '*'" >> /home/[your_username]/.jupyter/jupyter_notebook_config.py

(Note: this is one line of code! Only your browser breaks it into more lines!)

echo "c.NotebookApp.allow_remote_access = True" >> /home/[your_username]/.jupyter/jupyter_notebook_config.py

(Note: this is one line of code! Only your browser breaks it into more lines!)

These will add two lines to the freshly created config file that will make you able to use your Jupyter notebook from a browser window (like Chrome or Firefox).

Now you can go ahead and try Jupyter out by typing:

jupyter notebook --browser any

This command will start to run the Jupyter application on your remote server. While it’s running in Terminal, you should just open a browser and type this in the address bar:

[IP Address of your remote server from the email]:8888

So in my case I’ll type this to my Google Chrome’s address bar:
46.101.128.25:8888.

Well, it’s not a website but it looks like one. In reality, it just connects me to the interface of my Jupyter notebook that runs on my server.

data coding jupyter token

On this screen you need to type a password or a token first. As we haven’t generated any password (yet), you need to use the token, which you can easily find if you go back to your terminal window. Here:

data coding jupyter token command line

Note: The /?token= part should not be copied — only that part is needed that I annotated with green above.

If you manage to copy-paste your token, you will be logged into your Jupyter Notebook. And you can create your first Python Notebook on top right corner: “New” –» “Python 3

jupyter notebook create a new python3 notebook

On this surface you can try again printing the “Hello, World!” string. Once you have typed it, you can execute this command by hitting SHIFT+ENTER.

jupyter notebook hello world python3

And done! You have installed Python 3 and Jupyter Notebook — and you can come back and use them any time. Nice job!

Note 1: when you are done, don’t forget to shut down Jupyter in your Terminal window by hitting CTRL+C. If you want to use Jupyter again in the future do the same as above: type jupyter notebook --browser any and open a browser…

Note 2: this setup is not the most secure version of using Jupyter, so I’d suggest not  using any confidential data for now. (In another article, I’ll cover the security settings.)

Step 5: Install SQL and pgadmin4!

To continue with installing SQL, you should be back to Bash and the command line. You will know for sure, if you check the beginning of the line in your Terminal window (which is called the prompt, by the way). If you are on bash, it will look something like this (not necessarily green, it can be white or gray as well):

data coding bash commandline

If you are not, just double-check that you haven’t missed anything above… Or just hit CTRL+C several times (that’s the hotkey to skip every running process on your terminal screen).

(If somehow accidentally you are still in Python, you will see >>> at the beginning of the line. If so, hit CTRL + D.)

When you are back to Bash, you can set up postgreSQL fairly quickly using a similar apt-get command as before:

sudo apt-get install postgresql postgresql-contrib

(If it asks for your password, type it – if it asks whether to continue, say yes!)
Done! You have postgreSQL just like that. Let’s try to access it!

When you installed SQL, it automatically generated one more user on your server called postgres. This new user is an SQL superuser. And right now this is the only user who can access your freshly created SQL database. The good thing is that you can sign in to this superuser’s account with this command:

sudo -i -u postgres

Notice the small change on the prompt in the command line:

data coding command line prosgres

The superuser will be able to access SQL with this simple command (type it):

psql

You are in! You can run SQL commands and queries!

First thing first, let’s generate a new user, so you can access your database in the future with your normal user too (which is the preferred way).

CREATE USER [your_user_name] WITH PASSWORD '[your_preferred_password]';

It’s really important that you replace [your_user_name] with the very same new user name that you’ve used in bash. So in my case it will be:

CREATE USER dataguy WITH PASSWORD 'a_password_that_I_wont_put_into_this_article';

Since you are here, I recommend running one more command (you won’t need it now but it’ll become handy when you start with my SQL tutorial articles):

ALTER USER [your_user_name] WITH SUPERUSER;

Obviously, change [your_user_name] again with your user name.

For me it was:

ALTER USER dataguy WITH SUPERUSER;

This line will give your user SQL super user privileges – which will become handy when creating new SQL tables, etc. Don’t worry about it too much yet. It’s good that we have done it though.

Anyways, done! You can exit from postgreSQL and go back to bash! Type:

\q

(this is the exit command in postgres.)

Then you have to log out from the superuser as well and go back to your normal user! Type:

exit
data coding psql exit

Now, let’s login with your normal user to your SQL database with this command:

psql -U dataguy -d postgres

Great! You are back to SQL again! Let’s try it out and run these few SQL commands and queries:

CREATE TABLE test(column1 TEXT, column2 INT);
INSERT INTO test VALUES ('Hello', 111);
INSERT INTO test VALUES ('World', 222);
SELECT * FROM test;

The first line creates a new table called test. The 2nd and the 3rd load some test data in it. The 4th prints all the values to the screen from the test table!

You can learn about SQL from my SQL for Data Analysis tutorial series!

Exit from postgreSQL again:

\q

Install pgadmin4!

It’s time to install pgadmin! This is a desktop application for postgreSQL that you can use to access your SQL database from your personal computer (without connecting to your remote server in terminal) and write queries much more easily and efficiently. You will find this little SQL manager tool very useful when you start writing complex queries.

As a first step, make your remote server ready to connect by typing these 5 lines of code (copy-paste it one by one):

sudo -i -u root
echo "listen_addresses = '*'" >> /etc/postgresql/*/main/postgresql.conf

(Note: this is one line of code! Only your browser breaks it into 2 lines!)

echo 'host all all 0.0.0.0/0 md5' >> /etc/postgresql/*/main/pg_hba.conf

(Note: this is one line of code! Only your browser breaks it into 2 lines!)

sudo /etc/init.d/postgresql restart
exit

What you are doing here is logging in to the root user and making some modifications in the config files of postgreSQL. (Remember: as you are on your remote server, the changes you make won’t affect your personal computer!)

Then download pgadmin4 from here: pgadmin4.

Select your OS, then download, install and run it!

Once you are done, you will see something like this screen:

data coding pgadmin add server

Click the Add New Server Icon!

And fill in the popup:

data coding pgadmin connect

“GENERAL:”

  • “Name:” anything you want (eg. “Data36 Test Server“)

“CONNECTION:”

  • “Host name/address:” your remote server’s IP Address (in my case: 46.101.128.25)
  • “Port:” 5432
  • “Maintenance database:” postgres
  • “User name:” [your_user_name]
  • “Password:” your recently generated SQL password for your user

Click save and BOOM! You are connected to your database!

data coding pgadmin browse

At first sight, it’s not really straightforward, but you can discover the different folders on the left side. If you right click on the name of the server (on my screenshot: “Data36 Test Server”), you can disconnect from your server. And you can connect the same way, when you want to get back.
Also if you left click on one of your databases (on my screenshot: “postgres”), then you select on the top menu “Tools” –» “Query tool,” you will be able to run SQL queries (execute with the little Flash Icon):

data coding pgadmin sql queries

Notice that on my screenshot you can see the very same result that we got in the Terminal SQL!

Yay, you have SQL!

Now, at this point let me mention, that pgadmin4 is nice and free and built be the awesome postgreSQL team… but… to be honest, I don’t really use it in real life, because it’s a bit unstable — and generally speaking, there are better SQL manager tools. Here’s my favorite free SQL manager (and how to install it): SQL Workbench. (Note: Save this link for later, and now just finish the article with R.)

Only one small step left…

Step 6: Install R and RStudio!

UPDATE in 2020: When I first published this article, I figured that I’ll write some R tutorials to this blog, too. But in 2020, I realized that if you learn Python for data science, you won’t really need R. Regardless, I leave this R installation tutorial here — but by all means, feel free to skip it! Here’s why:

R is the easiest tool to set up! That’s why I left it to the end.

First use apt-get again to install R:

sudo apt-get install r-base-core

(If it asks for your password, type it – if it asks whether to continue, say yes!)

Now you have R. You can test the “Hello, World!” here as well! Start R first:

R

Then type:

print ("Hello, World!");
data coding r hello world

The syntax is a bit different than it was on Python and much different than it was in Bash. You can exit from R:

quit()

Save workspace image? [y/n/c] —» Say: n

There is an application for R as well to make your coding life easier. It’s called RStudio and you can set it up using these 3 lines of code (copy-paste them one by one)!

sudo apt-get install gdebi-core
wget https://download2.rstudio.org/rstudio-server-1.1.463-amd64.deb

sudo gdebi rstudio-server-1.1.463-amd64.deb

Then just go to your browser and type [your IP Address] and port 8787. In my case:

46.101.128.25:8787

You can login with your username (e.g. dataguy) and password. (The same, you were using to access your remote server so far.) And try “Hello, World!” here as well.

data coding rstudio hello world

You have installed R and RStudio, too! Congrats!

CONCLUSION

Nice job there!

You have created your own remote data server and you have installed Python, SQL, R and bash on it! This is a fantastic first step for you towards becoming a Data Scientist!

As I’ve mentioned several times during this article, I’ve been creating quite a few articles to show you how to use Python, SQL and bash. All of these start from the very basics. Feel free to start with any of these you prefer:

  1. SQL for Data Analysis tutorial series
  2. Python for Data Science tutorial series
  3. Bash for Analytics tutorial series

MORE:

Cheers,
Tomi Mester

*shout-out to Johann for finding, reporting and solving the issue!

Sources and further reading

Bash/Command Line:
Data Science At The Command Line: http://datascienceatthecommandline.com

R:
https://support.rstudio.com/hc/en-us/articles/200552306-Getting-Started

SQL:
https://www.cyberciti.biz/faq/howto-add-postgresql-user-account/
https://help.ubuntu.com/community/PostgreSQL
http://stackoverflow.com/questions/1287067/unable-to-connect-postgresql-to-remote-database-using-pgadmin

Python:
http://jupyter.readthedocs.io/en/latest/install.html
https://www.digitalocean.com/community/tutorials/how-to-set-up-a-jupyter-notebook-to-run-ipython-on-ubuntu-16-04