Replaced some throws to throwIOs where the type is IO

[ghc-base.git] / GHC / Float.lhs

diff --git a/GHC/Float.lhs b/GHC/Float.lhs
index d165088..c31be1b 100644 (file)
--- a/GHC/Float.lhs
+++ b/GHC/Float.lhs
@@ -1,5 +1,7 @@
 \begin{code}
 {-# OPTIONS_GHC -XNoImplicitPrelude #-}
+-- We believe we could deorphan this module, by moving lots of things
+-- around, but we haven't got there yet:
 {-# OPTIONS_GHC -fno-warn-orphans #-}
 {-# OPTIONS_HADDOCK hide #-}
 -----------------------------------------------------------------------------
@@ -247,7 +249,7 @@ instance  Floating Float  where
 
     asinh x = log (x + sqrt (1.0+x*x))
     acosh x = log (x + (x+1.0) * sqrt ((x-1.0)/(x+1.0)))
-    atanh x = log ((x+1.0) / sqrt (1.0-x*x))
+    atanh x = 0.5 * log ((1.0+x) / (1.0-x))
 
 instance  RealFloat Float  where
     floatRadix _        =  FLT_RADIX        -- from float.h
@@ -329,7 +331,7 @@ instance  Floating Double  where
 
     asinh x = log (x + sqrt (1.0+x*x))
     acosh x = log (x + (x+1.0) * sqrt ((x-1.0)/(x+1.0)))
-    atanh x = log ((x+1.0) / sqrt (1.0-x*x))
+    atanh x = 0.5 * log ((1.0+x) / (1.0-x))
 
 {-# RULES "truncate/Double->Int" truncate = double2Int #-}
 instance  RealFrac Double  where