Calculator - Tanja Stroble

calculator.rb

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+puts "Welcome to the calculator."
+puts "What operation would you like to perform?\n Your options are add(+), subtract(-),multiply(*),divide(/) or modulus(%).\n
+Enter either a symbol or the word itself.\n>"
+choice = gets.chomp.downcase
+
+#setting up math hash
+
+math = {
+  "add" => "+" ,
+  "subtract" => "-",
+  "multiply" => "*",
+  "divide" => "/",
+  "modulus" => "%",
+}
+
+# check if oeration is a valid input
+
+until math.has_key?(choice) || math.has_value?(choice)
+  puts "Please follow the instructions. "
+  choice = gets.chomp.downcase
+end
+
+#setting up operator
+
+if math.values.include? choice
+  operation = choice
+else
+  operation = math[choice]
+end
+
+# checking for valid number input
+
+def getnumber
+  num = gets.chomp
+  while true #controls for nil class
+    if num == "0"
+      return 0
+    elsif
+      num != 0
+      return num.include?(".") ? num.to_f : num.to_i
+    elsif
+      num[0] == "(" && num[-1] == ")"
+      return eval(num) #doesn't work
+    else
+      print "Please enter a valid number:"
+      num = gets.chomp
+    end
+  end
+end
+
+
+#getting number
+puts "Now enter numbers: "
+print "First number: "
+num1 = getnumber
+print "Second number: "
+num2 = getnumber
+
+# what if division of fixnums is less than 1? we don't want result to be zero
+# if  operation == "/" &&  num1 > num2
+#   solution = (num1).send(operation,(num2))
+# else
+#   num1 = num1.to_f
+#   num2 = num2.to_f
+# end
+
+if  operation == "/" &&  num2 > num1 ?  num1 = num1.to_f : #<= else
+  solution = (num1).send(operation,(num2))
+end
+
+if operation == "/" && num2 == 0
+  solution = "Undefined. Can't divide with zero."
+else
+  solution = (num1).send(operation,(num2))
+end
+
+if solution % 2 == 0 #if result is a zero decimal float, turn it into fixnum
+  solution = solution.to_i
+elsif solution > 0 && solution < 1
+  solution = solution.to_f
+end
+
+# neat output
+
+puts "#{num1} #{operation} #{num2} = #{solution}"