# R Statistical Analysis for Beginners

In this guide, I will help you learn R, the statistical programming language.

## Chapter 1

R is a programming language that can do many things. Visualizations, data processing, and manipulation of data are all easy for R. You can download R from r-project.org or from a package manager that you may use. It usually goes by the same name. It is maintained very well and has a lot of active users. Being free is also a major advantage. It runs on Windows, Mac, and Linux.

You do not use a compiler with R code. It is an interpreted language. Every statement is interpreted on a low level basis. However, interpreted languages are slower than those that use a compiler. This won’t make any difference at the beginning. Just keep it in mind if you decide to use it for more complicated tasks. It is not meant to be C++ as it does different things.

### The R Environment

We can use any text editor and many different IDE’s to write R code. Depending on your operating system, you will have a few different choices. Some of those include:

• RGui
• RStudio
• Eclipse
• Emacs
• Tinn-R
• R Commander
• Rattle for R

There are many more options to go with. These are some of the more well known that are free.

### Entering Commands

You can use R as a simple calculator if you want to. Enter an expression and hit enter.

3 + 54^2

After you enter your expression and hit enter, the interpreter returns an answer.  To close your session, type:

quit()

Our first session will complete the requisite “Hello World” program.

print (“Hello World”)

That is nice and easy, it only takes one line. Basic math is just as easy.

3^3 + 4^4

You should get the answer of 283. However, this is just the most basic usage and not really helpful.

### Starting With Vectors

A vector is a collection of the same type of things. If there are just numbers in the collection, it is called a numeric vector. To create a vector of numbers, you can type:

c(1,2,3,4,5,6,7)

This will create a vector of the numbers one through seven.

You can also create a vector with the sequence operator, a colon.

1:100

This expression creates a vector of numbers from one to a hundred. That is much quicker than typing them out. You can add all of them together by using the sum function.

sum(1:100)

### Variables and Vectors

We can store numbers and vectors in variables. This lets us store values to work on them at a later point. When they are stored, we can do calculations on them at any time.

x = 1:100x

The above statement assigns a vector to the variable “x”. Then we print the value of “x” with the next statement. We can create another variable and add it to the value of “x”.

a = 6^2x + a

### Interaction With User

We can get feedback from a user. To do this, we use the “readline()” function.

color = readline("What is your favorite color? ")paste (color)

Anytime you want to repeat some action, you should place the commands in a script. A script runs several commands at once. A script can run several calculations or ask for input. The only limit is your creativity.

To create a script, you need to open a script window. In Rstudio:

• In the top menu, click File
• Select New File
• Click R Script

This will open a window in the top left. You can paste the previous code into this window if you want. Save the file in the location that you prefer. Then, in the menu:

• Select Code
• Then click on Source towards the bottom

This will run the code in your bottom left window.