Python Scipy stats.frechet_r 示例说明

scipy.stats.frechet_r()是Frechet右(或Weibull最小值)连续随机变量，它使用标准格式和一些形状参数定义以完成其规格。

参数：
-> q :上下尾概率
-> a :形状参数
-> x :分位数
-> loc :[可选]位置参数。默认值= 0
-> scale:[可选]比例参数。默认值= 1
-> size :[int型元组，可选]形状或随机变量。
-> moments:[可选]由字母['mvsk']组成； “ m” =均值，“ v” =方差，“ s” = Fisher的偏度，“ k” = Fisher的峰度。 (默认=“ MV”)。

Results:弗雷切特右连续随机变量

代码1：创建Frechet右连续随机变量

from scipy.stats import frechet_r  
  
numargs = frechet_r .numargs 
[a] = [0.7, ] * numargs 
rv = frechet_r (a) 
  
print ("RV:\n", rv)  

输出：

RV:
 <scipy.stats._distn_infrastructure.rv_frozen object at 0x0000018D56769470>

代码2：Frechet右随机变量和概率分布。

import numpy as np 
quantile = np.arange (0.01, 1, 0.1) 
   
# Random Variates 
R = frechet_r .rvs(a, scale = 2,  size = 10) 
print ("Random Variates:\n", R) 
  
# PDF 
R = frechet_r .pdf(a, quantile, loc = 0, scale = 1) 
print ("\nProbability Distribution:\n", R)

输出：

Random Variates:
 [0.74797562 0.45139233 3.17050565 0.83673559 0.04150534 0.04417758
 0.08459631 0.58419257 4.88454049 3.68323048]

Probability Distribution:
 [0.00525539 0.05776573 0.11006225 0.16196069 0.21328776 0.26388153
 0.31359184 0.36228041 0.40982097 0.45609917]
 

代码3：图形表示。

import numpy as np 
import matplotlib.pyplot as plt 
  
distribution = np.linspace(0, np.minimum(rv.dist.b, 3)) 
print("Distribution:\n", distribution) 
  
plot = plt.plot(distribution, rv.pdf(distribution))

输出：

Distribution:
 [0.         0.06122449 0.12244898 0.18367347 0.24489796 0.30612245
 0.36734694 0.42857143 0.48979592 0.55102041 0.6122449  0.67346939
 0.73469388 0.79591837 0.85714286 0.91836735 0.97959184 1.04081633
 1.10204082 1.16326531 1.2244898  1.28571429 1.34693878 1.40816327
 1.46938776 1.53061224 1.59183673 1.65306122 1.71428571 1.7755102
 1.83673469 1.89795918 1.95918367 2.02040816 2.08163265 2.14285714
 2.20408163 2.26530612 2.32653061 2.3877551  2.44897959 2.51020408
 2.57142857 2.63265306 2.69387755 2.75510204 2.81632653 2.87755102
 2.93877551 3.        ]

代码4：更改位置参数

import matplotlib.pyplot as plt 
import numpy as np 
  
x = np.linspace(0, 5, 100) 
  
# Varying positional arguments 
y1 = frechet_r .pdf(x, 1, 3) 
y2 = frechet_r .pdf(x, 1, 4) 
plt.plot(x, y1, "*", x, y2, "r--")

输出：