Rotate point about another point in degrees python

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The following rotate function performs a rotation of the point point by the angle angle (counterclockwise, in radians) around origin, in the Cartesian plane, with the usual axis conventions: x increasing from left to right, y increasing vertically upwards. All points are represented as length-2 tuples of the form (x_coord, y_coord).

import math

def rotate(origin, point, angle):
    """
    Rotate a point counterclockwise by a given angle around a given origin.

    The angle should be given in radians.
    """
    ox, oy = origin
    px, py = point

    qx = ox + math.cos(angle) * (px - ox) - math.sin(angle) * (py - oy)
    qy = oy + math.sin(angle) * (px - ox) + math.cos(angle) * (py - oy)
    return qx, qy

If your angle is specified in degrees, you can convert it to radians first using math.radians. For a clockwise rotation, negate the angle.

Example: rotating the point (3, 4) around an origin of (2, 2) counterclockwise by an angle of 10 degrees:

>>> point = (3, 4)
>>> origin = (2, 2)
>>> rotate(origin, point, math.radians(10))
(2.6375113976783475, 4.143263683691346)

Note that there’s some obvious repeated calculation in the rotate function: math.cos(angle) and math.sin(angle) are each computed twice, as are px - ox and py - oy. I leave it to you to factor that out if necessary.

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