diff options
Diffstat (limited to 'Lib')
| -rw-r--r-- | Lib/random.py | 11 |
1 files changed, 6 insertions, 5 deletions
diff --git a/Lib/random.py b/Lib/random.py index ebab1f8..49921cb 100644 --- a/Lib/random.py +++ b/Lib/random.py @@ -182,12 +182,13 @@ def gauss(mu, sigma): # When x and y are two variables from [0, 1), uniformly # distributed, then # - # cos(2*pi*x)*log(1-y) - # sin(2*pi*x)*log(1-y) + # cos(2*pi*x)*sqrt(-2*log(1-y)) + # sin(2*pi*x)*sqrt(-2*log(1-y)) # # are two *independent* variables with normal distribution # (mu = 0, sigma = 1). # (Lambert Meertens) + # (corrected version; bug discovered by Mike Miller, fixed by LM) global gauss_next @@ -196,9 +197,9 @@ def gauss(mu, sigma): gauss_next = None else: x2pi = random() * TWOPI - log1_y = log(1.0 - random()) - z = cos(x2pi) * log1_y - gauss_next = sin(x2pi) * log1_y + g2rad = sqrt(-2.0 * log(1.0 - random())) + z = cos(x2pi) * g2rad + gauss_next = sin(x2pi) * g2rad return mu + z*sigma |