Help Bisection method Matlab

2 次查看（过去 30 天）

ilaria scanu 2022-6-12

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/1739050-help-bisection-method-matlab

评论： Torsten 2022-6-12

Exercise.PNG

Hi! I have to write a code using the bisection method. The teacher said to double check it because there is a mistake, but it looks fine to me. Could you please help me to find out what's wrong? The exercise is attached

Here is my code

a = 0.22; b = 0.08; % dimensions of the spring system [m]

K1 = 1600; % first spring system coefficient [N/m]

K2 = 1e5; % second spring system coefficient [N/m3]

L0 = sqrt(a^2+b^2); % initial spring length [m]

L = @(x) sqrt(a^2+(b+x).^2); % deformed spring length [m]

u = @(x) L(x)-L0; % deformed distance [m]

Fs = @(x) K1.*u(x)+K2.*u(x).^3; % applied force to deform spring [N]

W = @(x) 2.*Fs(x).*(b+x)./L(x); % weight force to deform the system of springs [N]

x0 = 0; xn = 0.25; % x interval

X = linspace(x0,xn);

plot(X,W(X)) % mass W in the interval X

hold on

Q = 400; % applied force to the system [N]

n = 100; % number of iterations to define root

for i = 1:n % Bisection method for an applied force Q in an interval X

xm = (x0+xn)/2; % estimated solution, midpoint of the interval

if (W(x0)-Q)*(W(xm)-Q) < 0 % check of which subinterval contains the solution

xn = xm;

else

x0 = xm;

end

plot(xm,W(xm),'*r') % plot of each estimated solution

end

3 个评论
显示 1更早的评论隐藏 1更早的评论

ilaria scanu 2022-6-12

I was asking mainly about the bisection, I think the mechanics of the physics should be correct

Torsten 2022-6-12

Except for that you should leave the bisection loop earlier than after 100 iterations (based on abs(W(xm)-Q) and abs(x0-xm)), I can't see anything wrong in your code.

请先登录，再进行评论。

请先登录，再回答此问题。