Question

我想知道是否有人知道如何将这个随机变量生成的VBA代码转换为Python。（“已保存”变量是VBA中的布尔值）

function MarsagliaBrayNormSRnd() As Double
Dim U1 As Double, U2 As Double
Dim x As Double, Y As Double

If Saved = False Then
   x = 2

   While x > 1
      U1 = (2 * Rnd() - 1)
      U2 = (2 * Rnd() - 1)
      x = (U1 * U1) + (U2 * U2)
   Wend

   Y = Sqr(-2 * Log(x) / x)
   MarsagliaBrayNormSRnd = U1 * Y
   SavedNormSRnd = U2 * Y
   Saved = True
Else
   MarsagliaBrayNormSRnd = SavedNormSRnd
   Saved = False
End If

End Function

我自己尝试了这段代码，但没有让它工作：

import math
import pandas as pd
import numpy as np

def MarsagliaBrayNormSRnd(u1,u1,x,y):
if Saved==False:
    x = 2

    while x > 1:
        np.random.seed(1)
        u1 = 2 * np.random.random((3,1)) - 1
        u2 = 2 * np.random.random((3,1)) - 1
        x = (u1 * u1) + (u2 * u2)   

    y = math.sqrt(-2 * math.log(x) / x)
    MarsagliaBrayNormSRnd = u1 * y
    SavedNormSRnd = u2 * y
    Saved = True
else:
    MarsagliaBrayNormSRnd = SavedNormSRnd
    Saved = False

Answer 1

不需要许多其他语言所需的真正可怕的结构！

from random import random
from numpy import sqrt, log

def MarsagliaBrayNormSRnd():
    while True:
        x = 2
        while x > 1:
            u1 = 2 * random() - 1
            u2 = 2 * random() - 1
            x = (u1 * u1) + (u2 * u2)   
        y = sqrt( -2 * log(x) / x )
        yield u1 * y
        yield u2 * y

for i, N in enumerate(MarsagliaBrayNormSRnd()):
    print (N)
    if i>10:
        break

Marsaglia bray，将VBA代码转换为Python

1 个答案: