用ODE函数解微分方程和用dsolve有什么区别?微分方程为:y''+4*y'+29y=0,y(0)=0,y'(0)=15这是用dsolvey = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(-3,3,100);yd = eval(y);plot(x,yd)这是用ODE函数:function dy=v
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![用ODE函数解微分方程和用dsolve有什么区别?微分方程为:y''+4*y'+29y=0,y(0)=0,y'(0)=15这是用dsolvey = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(-3,3,100);yd = eval(y);plot(x,yd)这是用ODE函数:function dy=v](/uploads/image/z/14839109-53-9.jpg?t=%E7%94%A8ODE%E5%87%BD%E6%95%B0%E8%A7%A3%E5%BE%AE%E5%88%86%E6%96%B9%E7%A8%8B%E5%92%8C%E7%94%A8dsolve%E6%9C%89%E4%BB%80%E4%B9%88%E5%8C%BA%E5%88%AB%3F%E5%BE%AE%E5%88%86%E6%96%B9%E7%A8%8B%E4%B8%BA%EF%BC%9Ay%27%27%2B4%2Ay%27%2B29y%3D0%2Cy%280%29%3D0%2Cy%27%280%29%3D15%E8%BF%99%E6%98%AF%E7%94%A8dsolvey+%3D+dsolve%28%27D2y%2B4%2ADy%2B29%2Ay%3D0%27%2C%27y%280%29%3D0%2CDy%280%29%3D15%27%2C%27x%27%29%3Bx+%3D+linspace%28-3%2C3%2C100%29%3Byd+%3D+eval%28y%29%3Bplot%28x%2Cyd%29%E8%BF%99%E6%98%AF%E7%94%A8ODE%E5%87%BD%E6%95%B0%EF%BC%9Afunction+dy%3Dv)
用ODE函数解微分方程和用dsolve有什么区别?微分方程为:y''+4*y'+29y=0,y(0)=0,y'(0)=15这是用dsolvey = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(-3,3,100);yd = eval(y);plot(x,yd)这是用ODE函数:function dy=v
用ODE函数解微分方程和用dsolve有什么区别?
微分方程为:y''+4*y'+29y=0,y(0)=0,y'(0)=15这是用dsolvey = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(-3,3,100);yd = eval(y);plot(x,yd)这是用ODE函数:function dy=vdp1000(t,y)dy=zeros(2,1);dy(1)=y(2);dy(2)=-4*y(2)-29*y(1);[T,Y]=ode15s('vdp1000',[-3,3],[0,15]);plot(T,Y(:,1),'-')他们的结果差距很大啊!
用ODE函数解微分方程和用dsolve有什么区别?微分方程为:y''+4*y'+29y=0,y(0)=0,y'(0)=15这是用dsolvey = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(-3,3,100);yd = eval(y);plot(x,yd)这是用ODE函数:function dy=v
数值解(ode系列)和解析解(即公式解,dsolve)的区别.查看原帖>>
回复xiaochao84 的帖子第二种方法求解(数值解)的时候把初值对错了,这样就可以了:y = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(0,3,100);yd = eval(y);plot(x,yd)hold onfun = @(t,y)[y(2);-4*y(2)-29*y(1)];[T,Y] = ode15s(f...
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回复xiaochao84 的帖子第二种方法求解(数值解)的时候把初值对错了,这样就可以了:y = dsolve('D2y+4*Dy+29*y=0','y(0)=0,Dy(0)=15','x');x = linspace(0,3,100);yd = eval(y);plot(x,yd)hold onfun = @(t,y)[y(2);-4*y(2)-29*y(1)];[T,Y] = ode15s(fun,linspace(0,3,100),[0,15]);plot(T,Y(:,1),'r-') 查看原帖>>
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变量代换把高阶微分方程化为一阶微分方程组,编写目标函数时顺序其实无所谓。 查看原帖>>