pub fn simpson2d<F, Y>( func: F, ax: f64, bx: f64, ay: f64, by: f64, divs: usize, ) -> Complex<f64>where F: Send + Sync + Fn(f64, f64) -> Y, Y: Into<Complex<f64>>,
Two dimensional simpson integration in x -> [a, b] and y -> [c, d] with divs slices on each axis
divs