candle.py

#!/usr/bin/env python

import colorsys
import time
from sys import exit

try:
    import numpy as np
except ImportError:
    exit('This script requires the numpy module\nInstall with: sudo pip install numpy')

import blinkt


blinkt.clear()
start = 0
end = 60
DELAY=0.01

while True:
    wait = np.random.choice(np.random.noncentral_chisquare(5, 1, 1000), 1)[0] / 50
    n = np.random.choice(np.random.noncentral_chisquare(5, 0.1, 1000), 1)
    limit = int(n[0])

    if limit > blinkt.NUM_PIXELS:
        limit = blinkt.NUM_PIXELS

    for pixel in range(blinkt.NUM_PIXELS):
        if pixel > limit:
            r, g, b = 0, 0, 0
        else:
            hue = start + (((end - start) / float(blinkt.NUM_PIXELS)) * pixel)
            r, g, b = [int(c * 255) for c in colorsys.hsv_to_rgb(hue / 360.0, 1.0, 1.0)]
        blinkt.set_pixel(pixel, r, g, b)

        if pixel < limit:
            time.sleep(DELAY / (pixel + 1))
            blinkt.show()
        if pixel == blinkt.NUM_PIXELS-1:
            blinkt.show()

    time.sleep(wait)
    #blinkt.clear()