python绘制简单彩虹图

from turtle import *
 
#控制彩虹路径
def path(pen, r, g, b):
  pen.penup()
  pen.goto(-400, -300)
  pen.pendown()
  pen.pencolor(r, g, b)
  pen.circle(1000, -180)
  pen.pensize(2)
  pen.right(0.05)
 
#绘制彩虹控制颜色
def Rainbow():
  pen = Turtle()
  pen.right(110)
  r = 255
  g = 0
  b = 0
  interval = 5
  colormode(255)
  # 由红到黄
  while g < 256:
    path(pen, r, g, b)
    g = g + interval
  #由黄到绿
  g = 255
  while r > 0:
    r = r - interval
    path(pen, r, g, b)
  #由绿到青
  r = 0
  while (b < 255 ):
    b = b + interval
    path(pen, r, g, b)
  b = 255
  #由青到蓝
  while (g > 0):
    g = g - interval
    path(pen, r, g, b)
  #由蓝到紫到红
  g = 0
  while r < 255:
    r = r + interval
    path(pen, r, g, b)
 
#文字输出
def TextFun():
  text = Turtle()
  text.hideturtle()
  text.color(\"red\")
  text.penup()
  text.setpos(100, -100)
  text.pendown()
  text.write(\"Rainbow\", False, align=\"center\", font=(\"  MT Bold\", 80, \"bold\"))
 
def main():
  setup(800, 600, 0, 0)
   (\"rainbow\")
  tracer(False)
  Rainbow()
  TextFun()
  tracer(True)
  mainloop()
 
if __name__ == \'__main__\':
  main()