Calculate the euclidian distance between an array of points to a line segment

lineseg_dists.py

def lineseg_dists(p, a, b):

    # Handle case where p is a single point, i.e. 1d array.
    p = np.atleast_2d(p)

    # TODO for you: consider implementing @Eskapp's suggestions
    if np.all(a == b):
        return np.linalg.norm(p - a, axis=1)

    # normalized tangent vector
    d = np.divide(b - a, np.linalg.norm(b - a))

    # signed parallel distance components
    s = np.dot(a - p, d)
    t = np.dot(p - b, d)

    # clamped parallel distance
    x = np.maximum.reduce([s, t, np.zeros(len(p))])

    # perpendicular distance component
    # switch to dot-prod method which is dimension-agnostic
    y = np.linalg.norm(p - b - t * d)

    # use hypot() to improve accuracy
    return np.hypot(x, y)

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