The following are my notes from the appacademy.io chapter 1 introduction to programming.
There are three types of data in Ruby:
- Numbers
- Booleans – True or false
- Strings – Words or phrases
Ruby is case sensitive
puts can be called methods in Ruby
Integers = Whole #s (ex 42)
Floats = Fractional #s (e.g. 3.14)
Never write commas when writing integers. They will change everything.
Notes on Division
Ruby does not divide into integers. It returns whole #s
puts (9.0/2) | #returns 4.5
puts (9.fdive(2)) | #returns 4.5
Modulo n%m -> returns the remainder from division
Defining Variables
ian_loves = “guitar, wifey, surfing”
Variables must:
- consist of letters or/and #s
- first character must be lowerCase
- no spaces (separate words w/ _ )
Gets Method
The gets method allows you to ask users to define variables
puts("Type in your name, please.")
name=gets()
puts(name)
This would return whatever the user entered
Gets for Strings and Integers
Converting Strings and Integers
- to_i = to integer
- to_s = to string
The Chomp Method
chomp makes it so a line break doesn’t happen behind each gets command. It seems like it’s used most of the time. For example:
puts("Type your name, please.")
name = gets
name = name.chomp
puts ("Hello" + name)
use gets.chomp rather than reassigning the variables.
Important Note: Feeling good about all of this. I can write program files using Atom and execute the files using terminal.
I went through the Codecademy command line class which was a critical step in understanding how to navigate and execute programs using just typing. This makes it so I can at least pretend to be like the guy in Mr. Robot.
It was today, November 20th, 2015 (these notes were copied her later) that I actually wrote and executed my first computer program. It was a game that said hello.
puts("Hello. What is your name, please?")
name = gets
name = name.chomp
puts("Hi " + name + ", it's nice to meet you.")
That’s it
If you’d like to continue to follow along with these notes, I continue the study in my notes in chapter 2.