lib/xirr/bisection.rb in xirr-0.2.7 vs lib/xirr/bisection.rb in xirr-0.2.8

@@ -11,10 +11,11 @@
     def xirr(midpoint = nil)
 
       # Initial values
       left = [BigDecimal.new(-0.99, Xirr::PRECISION), cf.irr_guess].min
       right = [BigDecimal.new(9.99, Xirr::PRECISION), cf.irr_guess + 1].max
+      @original_right = right
       midpoint ||= cf.irr_guess
       runs = 0
 
       # Loops until difference is within error margin
       while ((right - left).abs > Xirr::EPS && runs < Xirr.config.iteration_limit.to_i) do
@@ -27,11 +28,11 @@
       if runs >= Xirr.config.iteration_limit.to_i
         raise ArgumentError, "Did not converge after #{runs} tries."
       end
 
       # If enabled, will retry XIRR with NewtonMethod
-      if Xirr::FALLBACK && right_limit_reached?(right, midpoint)
+      if Xirr::FALLBACK && right_limit_reached?(midpoint)
         return NewtonMethod.new(cf).xirr
       end
 
       return midpoint.round Xirr::PRECISION
 
@@ -41,11 +42,11 @@
 
     # @param right [BigDecimal]
     # @param midpoint [BigDecimal]
     # @return [Boolean]
     # Checks if result is the right limit.
-    def right_limit_reached?(right, midpoint)
-      (right - midpoint).abs < Xirr::EPS
+    def right_limit_reached?(midpoint)
+      (@original_right - midpoint).abs < Xirr::EPS
     end
 
     # @param left [BigDecimal]
     # @param midpoint [BigDecimal]
     # @param right [BigDecimal]