Unlike Mac computers, Windows computers don't actually come with ruby. So lets download ruby to get the ball rolling!
Steps
- Visit this link.
- Download ruby version 2.1.7
- Make sure during the installation to check "Add Ruby executables to PATH", like so:
To double check if you have ruby installed, open your terminal and type in irb (ruby's repl) - it should load and you should be able to run ruby commands!
To run ruby files, simply type
irb -r ./path/to/file
This will load & run the file into the repl.
- Basic Ruby Practice
Check the documentation on Array, Hash and Enumerable as they could help tremendously with these exercises. :-)
Define a method sum(array) that takes an array of integers as an argument and returns the sum of its elements. For an empty array it should return zero.
Define a method max_2_sum(array) which takes an array of integers as an argument and returns the sum of its two largest elements. For an empty array it should return zero. For an array with just one element, it should return that element.
Define a method sum_to_n?(array) that takes an array of integers and an additional integer, n, as arguments and returns true if any two elements in the array of integers sum to n. An empty array should sum to zero by definition.
You can find starter code in lib/part1.rb.
- Strings
Define a method hello(name) that takes a string representing a name and returns the string "Hello, " concatenated with the name.
You can find starter code in lib/part2.rb.
- Object Oriented Example
Define a class BookInStock which represents a book with an ISBN
number, isbn, and price of the book as a floating-point number,
price, as attributes.
The constructor should accept the ISBN number (a string, since in real life ISBN numbers can begin with zero and can include hyphens) as the first argument and price as second argument. Include the proper getters and setters for these attributes.
Include a method price_as_string that returns the price of
the book formatted with a leading dollar sign and two decimal places, that is, a price
of 20 should format as "$20.00" and a price of 33.8 should format as
"$33.80".
You can find starter code in lib/part3.rb.