fun= @(thetha_P) ((1/(2*pi))*A_schnitt{e,1}{y,u}.*exp(-1i*r*thetha_P(y,u)));
A{e,y,u}= integral(fun,0,phi_e, 'ArrayValued',true)
integral() is going to call the given function. Normally it would pass in a vector of values, but because you indicated ArrayValued as true, integral() is going to pass in one value at a time.
Inside your anonymous function, that scalar value is going to be received as the variable thetha_P . As indicated, it will be a scalar. But you attempt to index it with thetha_P(y,u)
thetha_P which is a 3x63 double array.
Not inside that anonymous function it will not be. You said @(thetha_P) so inside the anonymous function thetha_P is what is passed in, not whatever value thetha_P might have in the workspace.
I have to ask what variable you are integrating with respect to? What value in fun is intended to range over 0 to phi_e with the integral being formed out of it?
