system of equations with elliptical integrals

Question

Nikhil 2013-11-5

0
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https://ww2.mathworks.cn/matlabcentral/answers/104905-system-of-equations-with-elliptical-integrals

回答： Walter Roberson 2013-11-5

Hello all,

I want to solve for 3 variables x,y,z. Three equations for these variables are as follows:

m=1-1/(x^2);
[Ki Ei]=ellipke(m);
eq1='((x^2+1)*z-y*2)/((x^2-1)*z)=0.9408';
eq2='y=Ki';
eq3='z=Ei';
[x0, y0, z0]=solve(eq1,eq2,eq3);

eq2 and eq3 are complete elliptical integrals of first and second kind. I have defined these integrals as variables because these are used in eq1. after running above code I am getting following error:

??? Error using ==> ellipke at 34 Inputs must be floats, namely single or double.

Can somebody suggest me what errors I am making in the code?? My aim is to solve for x,y,z. I have solved this using fsolve which requires initial guess of the solution. I want to solve for x,y,z without initial guess of the solution

Thanks in advance,

Nikhil