From 7f11632556b7a0a6248b08f471c06de3eb22452d Mon Sep 17 00:00:00 2001
From: ThibaultDECO <80053070+ThibaultDECO@users.noreply.github.com>
Date: Sun, 12 May 2024 00:47:01 +0200
Subject: [PATCH] Update statistics.py Faster

Faster
---
 Lib/statistics.py | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/Lib/statistics.py b/Lib/statistics.py
index c2f4fe8e054d3d..bcf4bd506ef40a 100644
--- a/Lib/statistics.py
+++ b/Lib/statistics.py
@@ -145,6 +145,7 @@
 from collections import Counter, namedtuple, defaultdict
 
 _SQRT2 = sqrt(2.0)
+_SQRT1_2 = sqrt(0.5)
 _random = random
 
 # === Exceptions ===
@@ -919,9 +920,9 @@ def kde(data, h, kernel='normal', *, cumulative=False):
 
         case 'normal' | 'gauss':
             sqrt2pi = sqrt(2 * pi)
-            sqrt2 = sqrt(2)
+            sqrt1_2 = sqrt(0.5)
             K = lambda t: exp(-1/2 * t * t) / sqrt2pi
-            W = lambda t: 1/2 * (1.0 + erf(t / sqrt2))
+            W = lambda t: 0.5 * (1.0 + erf(t * sqrt1_2))
             support = None
 
         case 'logistic':
@@ -1533,7 +1534,7 @@ def cdf(self, x):
         "Cumulative distribution function.  P(X <= x)"
         if not self._sigma:
             raise StatisticsError('cdf() not defined when sigma is zero')
-        return 0.5 * (1.0 + erf((x - self._mu) / (self._sigma * _SQRT2)))
+        return 0.5 * (1.0 + erf(((x - self._mu) * _SQRT1_2) / self._sigma))
 
     def inv_cdf(self, p):
         """Inverse cumulative distribution function.  x : P(X <= x) = p