次のモデルに SIQR を適用してみました。
SIR モデルの日本語表示 (その 2)
siqr02.py
#! /usr/bin/python
#
# siqr02.py
#
# May/14/2020
# ------------------------------------------------------------------
import matplotlib.pyplot as plt
import numpy as np
from scipy.integrate import odeint
from scipy.optimize import minimize
import sys
# ------------------------------------------------------------------
def SIQR_EQ(v, t, beta, gamma, p_kakuri):
q_kakuri = 0.0
rvalue = [0,0,0,0]
beta_ss_ii = beta * v[0] * v[1]
rvalue[0] = - beta_ss_ii
rvalue[1] = (1 - q_kakuri) * beta_ss_ii - p_kakuri * v[1] - gamma * v[1]
rvalue[2] = q_kakuri * beta_ss_ii + p_kakuri * v[1] - gamma * v[2]
rvalue[3] = gamma * v[1] + gamma * v[2]
# rvalue[3] = -(rvalue[0] + rvalue[1] + rvalue[2])
#
return rvalue
#
# ------------------------------------------------------------------
def calc_proc(times,beta_const,gamma_const,p_kakuri):
S_0=999
I_0=1
Q_0=0
R_0=0
ini_state = [S_0,I_0,Q_0,R_0]
args =(beta_const, gamma_const, p_kakuri)
N_total = S_0 + I_0 + Q_0 + R_0
R0 = N_total*beta_const *(1/gamma_const)
print(R0)
#Numerical Solution using scipy.integrate
#Solver SIR model
result = odeint(SIQR_EQ, ini_state, times, args)
#
return R0,result
# ------------------------------------------------------------------
def plot_graph_proc(R0,p_kakuri,times,result):
plt.rcParams["font.family"] = "TakaoExGothic"
# plt.rcParams["font.family"] = "IPAGothic"
str_out = "基本再生産数 : {}".format(format(R0,".3f"))
str_out += " "
str_out += "隔離率 : {}".format(format(p_kakuri,".3f"))
plt.title(str_out)
plt.xlabel('日数')
plt.ylabel('人数')
plt.plot(times,result)
plt.legend(['未感染者','感染 非隔離者','感染 隔離者','回復者'])
plt.show()
#
# ------------------------------------------------------------------
sys.stderr.write("*** start ***\n")
t_max = 160
dt = 0.01
#
beta_const = 0.2/1000
gamma_const = 0.1
p_kakuri = float(sys.argv[1])
sys.stderr.write("p_kakuri = %.3f\n" % p_kakuri)
times =np.arange(0,t_max, dt)
R0,result = calc_proc(times,beta_const,gamma_const,p_kakuri)
#
plot_graph_proc(R0,p_kakuri,times,result)
#
sys.stderr.write("*** end ***\n")
# ------------------------------------------------------------------
隔離率 0.0
./siqr02.py 0.0
![siqr02_01.png](https://qiita-image-store.s3.ap-northeast-1.amazonaws.com/0/179446/9fc18426-5326-9cf3-3509-3a7dd8e1eb1b.png)
隔離率 0.05
>```bash
./siqr02.py 0.0