#Question 6(a), (b), (d)
from neopixel import Neopixel
import time

NUM_LEDS = 16
pixels = Neopixel(NUM_LEDS, 0, 0, "GRB")
gradient = []

for i in range(NUM_LEDS):
    red = int((255*i)/(NUM_LEDS - 1))
    blue = 255 - red
    gradient.append((red, 0, blue))

for i in range(NUM_LEDS):
    pixels.set_pixel(i, gradient[i])

pixels.show()

while True:
    for _ in range(NUM_LEDS):
        pixels.rotate_right(1)
        pixels.show()
        time.sleep(0.5)

    for _ in range(NUM_LEDS):
        pixels.rotate_left(1)
        pixels.show()
        time.sleep(0.5)