Z is an (n, 2) array of cartesian (x, y) coordinates. Return an (n, 2) array of polar coordinates (R, T) where R = sqrt(x²+y²) and T = arctan2(y, x).
Z
(n, 2)
(x, y)
(R, T)
R = sqrt(x²+y²)
T = arctan2(y, x)
solve(...)