python泊松分布公式和期望_当λ很大时泊松分布如何计算？

你的名字 2023-01-09 01:27 144阅读 0赞

用Python计算：

import math

from scipy import stats

\#调用函数直接计算

p = stats.poisson.pmf(200, 300)

print("λ=300，k=200概率：",p)

kj = 1 \#k! k阶乘

for i in range(1, 200+1):

kj\*=i

print("k=200的阶乘：",kj,"\\n")

powlmk=300\*\*200

print("λ=300的k=200次方：",powlmk,"\\n")

elm=math.e\*\*(-300)

print("e的-300次方：",elm,"\\n")

pk=powlmk/kj\*elm

print("最终结果：",pk)

λ=300，k=200概率： 1.733874793103563e-10

k=200的阶乘： 788657867364790503552363213932185062295135977687173263294742533244359449963403342920304284011984623904177212138919638830257642790242637105061926624952829931113462857270763317237396988943922445621451664240254033291864131227428294853277524242407573903240321257405579568660226031904170324062351700858796178922222789623703897374720000000000000000000000000000000000000000000000000

λ=300的k=200次方： 2656139888758747693387813220357796268292334526533944959745749617390924909013021829943846990440010000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000

e的-300次方： 5.148200222412096e-131

最终结果： 1.7338747931034605e-10