webbpsf_ext.coords.xy_to_rtheta

webbpsf_ext.coords.xy_to_rtheta(x, y)

Convert (x,y) to (r,theta)

Input (x,y) coordinates and return polar cooridnates that use the STPSF convention (theta is CCW of +Y)

Input can either be a single value or numpy array.

Parameters:

• x (float or array) – X location values

• y (float or array) – Y location values