gistfile1.rb

#!/usr/bin/env ruby
 
#Ask the user for a number to test if it is a prime number or not 
puts "Pleas input a number to test if its a prime number: "
input_number = gets.to_f

#Ensure that the user doesn't put in zero as zero isn't a prime (division by zero)
#Also note that by some definitions negative numbers are in fact prime numbers and therefore valid
while input_number == 0
 puts "You submitted and invalid number or zero, please input a different number: "
 input_number = gets.to_f
end

#Method for testing if a given number is prime or not
def is_prime(input_number)
  divisible_counter = 0
  (1..input_number).each do |x|
   if input_number % x == 0
     divisible_counter += 1
     return false if divisible_counter > 2
   end
  end
  true
end

#Show the results of our test
results = is_prime(input_number)
puts "\n#{results}"