用matlab怎么求一阶微分方程啊 如何用matlab求下面一阶微分方程组的数值解
MATLAB \u4e2d \u4e00\u9636\u5fae\u5206\u65b9\u7a0b\u5982\u4f55\u753b\u56feI use Matlab code to reply your question. You should run successfully by pasting it into your code file.
In order to use built-in function of ODE45, I first off set a function file called 'myode.m'
function [xp]=myode(t,x) xp=-exp(-x)*cos(x);end
Then you need to create a new file and put this code inside.
[t,x]=ode45(@myode,[0,5],1);plot(t,x)
The plot result should look like
Have a happy haunting :-)
\u7528matlab\u6c42\u4e0b\u9762\u4e00\u9636\u5fae\u5206\u65b9\u7a0b\u7ec4\u7684\u6570\u503c\u89e3
\u6b64\u5fae\u5206\u65b9\u7a0b\u53ef\u4ee5\u7528ode45\uff08\uff09\u51fd\u6570\u6c42\u7684\u5176\u6570\u503c\u89e3\u3002\u5176\u89e3\u8fc7\u7a0b\u4e3a
y =9*exp(-2)*exp(x) + 1
绛旓細鍦∕atlab涓嬭緭鍏ワ細edit锛岀劧鍚庡皢涓嬮潰涓よ鐧惧垎鍙蜂箣闂寸殑鍐呭锛屽鍒惰繘鍘伙紝淇濆瓨 function dy=zhidao_kingwolfnet(t,y)y濡傛灉鍦ㄤ綘鐨勫尯闂碵-0.0015,0.0015],鐢ㄤ綘鐨刬鐨勮〃杈惧紡,涓嶅湪鍖洪棿鍐呯殑璇,鎴戠洿鎺ュ皢i璧嬫垚0 if ((y>=-0.0015)&&(y<=0.0015))i=(0.0006455*exp(0.4182*(10*y/0.001+21)) + ...
绛旓細t+1/y-log(y)+log(-1+y)+C1=0 dsolve('Df = f + sin(t)', 'f(pi/2) = 0')dsolve('D2y = -a^2*y', 'y(0) = 1, Dy(pi/a) = 0')S = dsolve('Dx = y', 'Dy = -x', 'x(0)=0', 'y(0)=1')S = dsolve('Du=v, Dv=w, Dw=-u','u(0)=0, v(...
绛旓細y =9*exp(-2)*exp(x) + 1
绛旓細鍦∕atlab涓嬭緭鍏ワ細edit锛岀劧鍚庡皢涓嬮潰涓よ鐧惧垎鍙蜂箣闂寸殑鍐呭锛屽鍒惰繘鍘伙紝淇濆瓨 function dxdt=zhidao_rk4_5(t,x)global a b c d r x1=x(1);x2=x(2);x3=x(3);x4=x(4);dxdt=[a*(x2-x1)+x4;d*x1-x1*x3+c*x2;x1*x2-b*x3;x2*x3+r*x4;];鍦∕atlab涓嬮潰杈撳叆锛歡lobal a b c d ...
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绛旓細clear allclc f=@(t,y)(-3*cos(2*t)+9*sin(t)+t);tspan=0:.05:5;[t,y1]=ode45(f,tspan,0);y2=tspan.^2/2 - 9*cos(tspan) - (3*sin(2*tspan))/2 + 9plot(tspan,y1,tspan,y2,'r+'),legend('鏁板艰В','瑙ｆ瀽瑙')鍩烘湰鏄竴鏍风殑 ...
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