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How would I add a radial gradient at the top of the cylinder?
I have two functions, fun1[a1,a2,b1,b2,b] and fun2[a1,a2,b1,b2,b]=0. Where both equations are nonlinear. I am trying to optimize fun1 using differential evolution where b is root of fun2 for the current values of a1, a2, b1 and b2. I tried...