Day 5: Poisson Distribution I

In this challenge, we learn about Poisson distributions. Check out the Tutorial tab for learning materials!

A random variable, , follows Poisson distribution with mean of . Find the probability with which the random variable is equal to .

The first line contains 's mean. The second line contains the value we want the probability for:

2.5
5

If you do not wish to read this information from stdin, you can hard-code it into your program.

Print a single line denoting the answer, rounded to a scale of decimal places (i.e., format).



In [19]:

    
import math
from matplotlib import pylab as plt
%matplotlib inline



In [20]:

    
def posion_dist(m, k):
    return (m**k * math.e**(-m)) / math.factorial(k)

Acme Realty company sells an average of 2 homes per day.

What is the probability that exactly 3 homes will be sold tomorrow?



In [34]:

    
posion_dist(2, 3)









    Out[34]:





0.1804470443154836



In [30]:

    
N = range(1, 20)
M = 7
plt.plot(N, [posion_dist(M, i) for i in N])









    Out[30]:





[<matplotlib.lines.Line2D at 0x10a4db358>]