solve the question ( fsolve , vpasolve)

Question

onur karakurt 2021-5-22

0
链接

此问题的直接链接

https://ww2.mathworks.cn/matlabcentral/answers/837113-solve-the-question-fsolve-vpasolve

编辑： Torsten 2021-5-23

is there any other way to solve the equation below.

clear all;clc;
a=0.5;
x=linspace(-2*a,2*a,100);
eqn=@(x,y,a)(y.^2./(x.^2+y.^2)).*(1-2.*(1-(x./(2*a)).^2-(y./(2*a)).^2))-(y./a).^2;
for k = 1:numel(x)
    options = optimoptions('fsolve','Display','iter');
    yv(k,:) = fsolve(@(y)eqn(x(k),y,a), 1, options);
end
plot(x,yv)

when ı change initial value for iteration, answers and graph is changing.

3 个评论
显示 1更早的评论隐藏 1更早的评论

Torsten 2021-5-23

编辑：Torsten 2021-5-23

If you multiply your equation by x^2+y^2, you see that you try to solve a quadratic equation in y^2. This equation might have 0, 1, 2 or 4 real solutions. Use symbolic computation using "solve" instead of "fsolve" to sort out the solution that makes sense for your problem.