使用MATLAB积分求解方程

Question

I would like to solve an equation below using MATLAB:

All the parameters except p are known, so I only need to solve for p. However since I need to consider the sign of the integrand and there is an absolute value sign in it I don't know how to solve it. Could anyone please help? Thank you.

Answer 1

This is an interesting question, so I'll give it a stab. Just out of own curiosity, what equation is this?

%This code just displays an error about not enough input arguments in line 4.  I'm still working on fixing this bug, but wanted to provide an update.
function y = yourFunc(m,q,t,p)
    if exist('p') == 0
        syms p
        fun = @(theta,p) ((1/pi) .* sign( 1 - p + (q .* sind(t))) .* (abs(1 - p + (q .* sind(t))) .^ m));
        eqn = (integral(@(theta)fun(theta,p),(-pi/2),(pi/2)) == 1);
        y = solve(eqn,p);
    end
end

function x = runCode()
    x = yourFunc(10,0.5,0:10:90)
end

Are your parameters vectors? I am unsure, but this code should work for elementwise operations anyway. I also put 1/pi in the integrand since it's a constant and isn't integrated anyway. Also, a caveat: I have never seen the "sign" function in your integrand so I put it in the code, but I'm not entirely sure what math symbol it is. I don't have MATLAB in front of me right now, but I think this should work; if you have any problems with it please comment and I'll fix my code. Good luck with your project!

Solve Documentation , Integral Documentation