matlab-(含教程)基于龙格库塔算法的SIR新冠病毒疫情预测matlab仿真

clc; clear; close all; warning off; addpath(genpath(pwd)); a = 1; b = 215; R_0 = 2.79; population = 9969510; vaccinated = 2387785; i_0 = 116; r_0 = 1232727; gamma = 1/10; s_0 = population - vaccinated - r_0; beta = (R_0*gamma)/(s_0); y = [s_0, i_0, r_0]; f = @(t,y) [-beta*y(1)*y(2); y(2)*(beta*y(1) - gamma); gamma*y(2)]; [t,w] = rk4(a,b,360,y,f); figure(1) hold on; plot(t,w,"LineWidth",2); legend('Susceptible','Infected','Recovered'); title('COVID-19 Los Angeles'); xlabel('Time (days)'); ylabel('Population'); a = 1; b = 215; R_0 = 2.79; population = 9969510; vaccinated = 0; i_0 = 116; r_0 = 1232727; gamma = 1/10; s_0 = population - vaccinated - r_0; beta = (R_0*gamma)/(s_0); y = [s_0, i_0, r_0]; f = @(t,y) [-beta*y(1)*y(2); y(2)*(beta*y(1) - gamma); gamma*y(2)]; [t,w] = rk4(a,b,360,y,f); figure(2) hold on; plot(t,w,"LineWidth",2); legend('Susceptible','Infected','Recovered'); title('Scenario 1 COVID-19 Model'); xlabel('Time (days)'); ylabel('Population'); a = 1; b = 215; R_0 = 2.79; population = 9969510; vaccinated = population * .6; i_0 = 116; r_0 = 1232727; gamma = 1/10; s_0 = population - vaccinated - r_0; beta = (R_0*gamma)/(s_0); y = [s_0, i_0, r_0]; f = @(t,y) [-beta*y(1)*y(2); y(2)*(beta*y(1) - gamma); gamma*y(2)]; [t,w] = rk4(a,b,360,y,f); figure(3) hold on; plot(t,w,"LineWidth",2); legend('Susceptible','Infected','Recovered'); title('Scenario 2 COVID-19 Models'); xlabel('Time (days)'); ylabel('Population'); a = 1; b = 215; R_0 = 6.68; population = 9969510; vaccinated = 2387785; i_0 = 116; r_0 = 1232727; gamma = 1/10; s_0 = population - vaccinated - r_0; beta = (R_0*gamma)/((s_0)); y = [(s_0), i_0, r_0]; f = @(t,y) [-beta*y(1)*y(2); y(2)*(beta*y(1) - gamma); gamma*y(2)]; [t,w] = rk4(a,b,360,y,f); figure(4) hold on; plot(t,w,"LineWidth",2); legend('Susceptible','Infected','Recovered', 'FontSize'); title('Scenario 3 COVID-19 Model'); xlabel('Time (days)'); ylabel('Population');