Solving integral equation with double ingegrals and singularities

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SUMMARY

The discussion focuses on solving a complex integral equation involving double integrals and singularities, specifically the equation f(x,y,w) = 137.03*y^2/((0.238*exp(0.067*y^2)+1)*(w-5.26*xy-2.63)*(w-5.26*xy+2.63)) = 1 + 8478/(10828-w^2-1.13*j*w). The user attempts to find the complex variable w using MATLAB's dblquad and fsolve functions. The recommended approach includes a brute-force search in the complex plane, starting with a circle around the origin and iteratively refining the search to minimize the difference between the left-hand side and right-hand side of the equation.

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srabbaa66
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Hello
I need help to solve the following integral equation:
f(x,y,w)=137.03.*y.^2./((0.238.*exp(0.067.*y.^2)+1).*(w-5.26.*x.*y-2.63).*(w-5.26.*x.*y+2.63))=1+8478./(10828-w.^2-1.13.*j.*w)
xmin=-1, xmax.=1, ymin=0, ymax=inf (nad can be taken 500 because the function decreases rapidly)
I want to find w which is complex number.
I tried the following code:
f=@(w) dblquad(@(x,y) 137.03.*y.^2./((0.238.*exp(0.067.*y.^2)+1).*(w-5.26.*y.*x-2.63).*(w-5.26.*y.*x+2.63)),-1,1,0,100)-1-8478./(10828-w.^2-j.*w.*1.13)
V=fsolve(f,160)
There are some singularities. How can I solve the problem
 
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Looks like you have:

g(w)=\int\int f(w,x,y)dxdy

for complex w. Then unless someone can suggest an analytical approach, I would recommend a brute-force search in the complex plane for w. Start with a circle about the origin. Say 100 points around it. Compute both sides. Find the minimum absolute value of the difference between the RHS and LHS. That the current point. Now take a small circle around that point, another 100 points, find the minimum again. Keep doing this and I think the trajectory will lead to the solution unless some problems are encountered.
 

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