def color_scale()

in chartify/_core/colour.py [0:0]

• 9 lines of code
• 7 McCabe index (conditional complexity)

def color_scale(begin_hsl, end_hsl, nb):
    """Returns a list of nb color HSL tuples between begin_hsl and end_hsl

    >>> from colour import color_scale

    >>> [rgb2hex(hsl2rgb(hsl)) for hsl in color_scale((0, 1, 0.5),
    ...                                               (1, 1, 0.5), 3)]
    ['#f00', '#0f0', '#00f', '#f00']

    >>> [rgb2hex(hsl2rgb(hsl))
    ...  for hsl in color_scale((0, 0, 0),
    ...                         (0, 0, 1),
    ...                         15)]  # doctest: +ELLIPSIS
    ['#000', '#111', '#222', ..., '#ccc', '#ddd', '#eee', '#fff']

    Of course, asking for negative values is not supported:

    >>> color_scale((0, 1, 0.5), (1, 1, 0.5), -2)
    Traceback (most recent call last):
    ...
    ValueError: Unsupported negative number of colors (nb=-2).

    """

    if nb < 0:
        raise ValueError("Unsupported negative number of colors (nb=%r)." % nb)

    step = tuple([float(end_hsl[i] - begin_hsl[i]) / nb for i in range(0, 3)]) if nb > 0 else (0, 0, 0)

    def mul(step, value):
        return tuple([v * value for v in step])

    def add_v(step, step2):
        return tuple([v + step2[i] for i, v in enumerate(step)])

    return [add_v(begin_hsl, mul(step, r)) for r in range(0, nb + 1)]