From f5e2855d1adee3739d1cf6a14e4e30bb3aa604c2 Mon Sep 17 00:00:00 2001
From: haydenwilliams <hwilliams.deva@gmail.com>
Date: Wed, 8 Aug 2018 10:11:25 -0700
Subject: [PATCH] Create calculator.rb

---
 calculator.rb | 143 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 143 insertions(+)
 create mode 100644 calculator.rb

diff --git a/calculator.rb b/calculator.rb
new file mode 100644
index 0000000..21bafea
--- /dev/null
+++ b/calculator.rb
@@ -0,0 +1,143 @@
+# define methods / acceptable operators
+def add(x, y)
+  return x + y
+end
+
+def subtract(x, y)
+  return x - y
+end
+
+def divide(x, y)
+  return x / y
+end
+
+def multiply(x, y)
+  return x * y
+end
+
+def exponent(x, y)
+  return x ** y
+end
+
+def modulo(x, y)
+  return x % y
+end
+
+acceptable_operators = ["add", "+", "subtract", "-", "divide", "/", "multiply", "*", "exponent", "^", "modulo", "%"]
+
+# intro / choose operator
+puts "Hi! Welcome to the calculolator app :) I will help you perform simple (and not so simple!) calculolations :) :)"
+
+puts """\nPlease choose which operation you would like to perform:
+
+(you may type either the name of the operator or its symbol)
+
+Add (+)
+Subtract (-)
+Divide (/)
+Multiply (*)
+Exponent (^)
+Modulo (%)
+"""
+
+operation = gets.chomp.downcase
+
+# verify operator
+until acceptable_operators.include?(operation)
+
+  puts "\nSorry, what you typed was not an acceptable operation. Perhaps you made a typo?"
+
+  operation = gets.chomp
+
+end
+
+# convert operator symbols
+case operation
+  when "add"
+    operation = "+"
+
+  when "subtract"
+    operation = "-"
+
+  when "multiply"
+    operation = "*"
+
+  when "divide"
+    operation = "/"
+
+  when "exponent"
+    operation = "^"
+
+  when "modulo"
+    operation = "%"
+
+end
+
+# clear console
+system "clear" or system "cls"
+
+# take values from user
+puts "\nPlease input the first number from your equation (this number will be acted upon by the second number):"
+
+first_num = gets.chomp
+
+puts "\nPlease input the second number from your equation (this number will act upon the first number):"
+
+second_num = gets.chomp
+
+# use regex to check for erroneous values (sadly unsure how to write regular expression that allows input of floats while also preventing input of non-numerical characters D:)
+while first_num.scan(/\D/).empty? == false || second_num.scan(/\D/).empty? == false || first_num == "" || second_num == ""
+  puts "\nOh no! It looks like you screwed something up! Let's try it again ok?"
+
+  puts "First number:"
+  first_num = gets.chomp
+
+  puts "Second number:"
+  second_num = gets.chomp
+end
+
+# convert num strings to float
+first_num = first_num.to_f
+second_num = second_num.to_f
+
+# verify divide by zero
+if operation == "/" && second_num == 0
+  puts "\nOh no! It looks like you are trying to divide by zero! Unfortunately, this is contrary to Intergalactic Law and I will have to request that you choose a new number to divide your first number by."
+
+  while second_num == 0
+    puts "Second number:"
+
+    second_num = gets.chomp.to_f
+  end
+end
+
+# perform calculation
+if operation == "+"
+  result = add( first_num, second_num )
+
+elsif operation == "-"
+  result = subtract( first_num, second_num )
+
+elsif operation == "*"
+  result = multiply( first_num, second_num )
+
+elsif operation == "/"
+  result = divide( first_num, second_num )
+
+elsif operation == "^"
+  result = exponent( first_num, second_num )
+
+elsif operation == "%"
+  result = modulo( first_num, second_num )
+
+end
+
+# clear console
+system "clear" or system "cls"
+
+# output formula / result
+puts "\nAlright, here are the results of your calculation!"
+
+puts "#{first_num} #{operation} #{second_num} = #{result}"
+
+puts "I hope you're pleased with yourself! I know I am!"