From f72bb57fff29609336beae56ae148e20d0dd702e Mon Sep 17 00:00:00 2001
From: Josep Sanjuas <jsanjuas@gmail.com>
Date: Sat, 18 Apr 2015 13:40:20 +0200
Subject: [PATCH] Convert to float before sum

---
 lib/pure/math.nim | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/pure/math.nim b/lib/pure/math.nim
index 05c2cf57cb..9bd5945498 100644
--- a/lib/pure/math.nim
+++ b/lib/pure/math.nim
@@ -117,10 +117,11 @@ proc sum*[T](x: openArray[T]): T {.noSideEffect.} =
 template toFloat(f: float): float = f
 
 proc mean*[T](x: openArray[T]): float {.noSideEffect.} =
-  ## computes the mean of the elements in `x`. 
+  ## computes the mean of the elements in `x`, which are first converted to floats.
   ## If `x` is empty, NaN is returned.
   ## ``toFloat(x: T): float`` must be defined.
-  result = toFloat(sum(x)) / toFloat(len(x))
+  for i in items(x): result = result + toFloat(i)
+  result = result / toFloat(len(x))
 
 proc variance*[T](x: openArray[T]): float {.noSideEffect.} =
   ## computes the variance of the elements in `x`.