lib/dydx/algebra/operator/parts/general.rb in dydx-0.0.7 vs lib/dydx/algebra/operator/parts/general.rb in dydx-0.0.8

@@ -21,13 +21,13 @@
                 case operator
                 when :+ then _(2) * self
                 when :* then self ^ _(2)
                 when :^ then super(x)
                 end
-              elsif operator == :+ && inverse?(x, :+)
+              elsif operator == :+ && inverse?(:+, x)
                 e0
-              elsif operator == :* && inverse?(x, :*)
+              elsif operator == :* && inverse?(:*, x)
                 e1
               elsif [:+, :*].include?(operator) && x.send("#{to_str(operator)}?")
                 if combinable?(x.f, operator)
                   send(operator, x.f).send(operator, x.g)
                 elsif combinable?(x.g, operator)
@@ -41,23 +41,15 @@
                 elsif combinable?(x.x.g, operator)
                   send(operator, inverse(x.x.g, operator)).send(operator, inverse(x.x.f, operator))
                 else
                   super(x)
                 end
-              elsif [:*].include?(operator) && x.subtrahend?
+              elsif [:*].include?(operator) && x.inverse?(:+)
                 inverse(::Algebra::Formula.new(self, x.x, operator.to_sym), :+)
               else
                 super(x)
               end
             end
-          end
-
-          def to_str(operator)
-            {
-              addition:       :+,
-              multiplication: :*,
-              exponentiation: :^
-            }.key(operator)
           end
         end
       end
     end
   end