Closed. This question needs to be more focused. It is not currently accepting answers. Want to improve this question? Update the question so it focuses on one problem only by editing this post. Closed 7 years ago. Improve this question I like Ruby on Rails and I use it for all my web development projects. … Read more
I want to create different methods for a class called Multiset. I have all the required methods, but I’m unsure of how to write intersection, union, and subset methods. For intersection and union, my code starts like this: def intersect(var) x = Multiset.new end Here is an example: X = [1, 1, 2, 4] Y … Read more
How do you round a float to 2 decimal places in JRuby(1.6.x)? number = 1.1164 number.round(2) # The above shows the following error # wrong number of arguments (1 for 0) 6 Answers 6
Here is some code: class Person def initialize(age) @age = age end def age @age end def age_difference_with(other_person) (self.age – other_person.age).abs end protected :age end What I want to know is the difference between using @age and self.age in age_difference_with method. 6 Answers 6
Example: [12,23,987,43 What is the fastest, most efficient way to remove the “[“, using maybe a chop() but for the first character? 15 Answers 15
arr is array of strings: [“hello”, “world”, “stack”, “overflow”, “hello”, “again”] What would be an easy and elegant way to check if arr has duplicates, and if so, return one of them (no matter which)? Examples: [“A”, “B”, “C”, “B”, “A”] # => “A” or “B” [“A”, “B”, “C”] # => nil 23 Answers 23
I’m trying to create a new file and things don’t seem to be working as I expect them too. Here’s what I’ve tried: File.new “out.txt” File.open “out.txt” File.new “out.txt”,”w” File.open “out.txt”,”w” According to everything I’ve read online all of those should work but every single one of them gives me this: ERRNO::ENOENT: No such file … Read more
List the ruby versions console:~$ rvm list rvm rubies ruby-2.0.0-p481 [ i686 ] # => – current # =* – current && default # * – default Try to use a specific version of ruby console:~$ rvm use 2.0.0 RVM is not a function, selecting rubies with ‘rvm use …’ will not work. You need … Read more
This question already has answers here: Difference between “and” and && in Ruby? (8 answers) Closed 2 years ago. What’s the difference between the or and || operators in Ruby? Or is it just preference? 8 Answers 8
There are instances where I would like to revert and uninstall all previous gem installations. For instance, I needed to assist a friend migrate their rails development machine to use RVM. As they had been previously using the system-wide gem, he was experiencing many headaches when working with multiple projects. Essentially, he was the poster-child … Read more
