CPP

vector to angle

// note that Y is first
rad = atan2(y, x)
deg = atan2(y, x)*180/pi

vector from angle

# to get a vector from an angle, implement something like the code below:

vector = Vector2(cos(theta), sin(theta))

# if this doesn't give accurate results, check whether you are using the right
# angle units for the function (degs or rads) and if it is flipped around the
# mirror line y=x swap the cos ans sin functions.