Remove assumptions on the Normed class.

[numerical-analysis.git] / src / Roots / Fast.hs

diff --git a/src/Roots/Fast.hs b/src/Roots/Fast.hs
index 78c299ad6a2cc39629b409bff5eed86787a3ca20..0deb1fd6237a5909ea7d15a252f09b524093d1bf 100644 (file)
--- a/src/Roots/Fast.hs
+++ b/src/Roots/Fast.hs
@@ -14,6 +14,8 @@ import Normed
 
 import NumericPrelude hiding (abs)
 import qualified Algebra.Absolute as Absolute
 
 import NumericPrelude hiding (abs)
 import qualified Algebra.Absolute as Absolute

+import qualified Algebra.Additive as Additive
+import qualified Algebra.Algebraic as Algebraic

 import qualified Algebra.Field as Field
 import qualified Algebra.RealRing as RealRing
 import qualified Algebra.RealField as RealField
 import qualified Algebra.Field as Field
 import qualified Algebra.RealRing as RealRing
 import qualified Algebra.RealField as RealField


@@ -116,9 +118,9 @@ fixed_point_iterations f x0 =
 --   We also return the number of iterations required.
 --
 fixed_point_with_iterations :: (Normed a,
 --   We also return the number of iterations required.
 --
 fixed_point_with_iterations :: (Normed a,

-                                Field.C b,
-                                Absolute.C b,
-                                Ord b)
+                                Algebraic.C a,
+                                RealField.C b,
+                                Algebraic.C b)

                             => (a -> a)  -- ^ The function @f@ to iterate.
                             -> b        -- ^ The tolerance, @epsilon@.
                             -> a        -- ^ The initial value @x0@.
                             => (a -> a)  -- ^ The function @f@ to iterate.
                             -> b        -- ^ The tolerance, @epsilon@.
                             -> a        -- ^ The initial value @x0@.