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9c01db40aa
Co-authored-by: Wulian <xiguawulian@gmail.com> Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
58 lines
911 B
Python
58 lines
911 B
Python
"""turtledemo/chaos.py
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A demonstration of chaos.
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"""
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from turtle import *
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N = 80
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def f(x):
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return 3.9*x*(1-x)
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def g(x):
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return 3.9*(x-x**2)
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def h(x):
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return 3.9*x-3.9*x*x
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def jumpto(x, y):
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penup(); goto(x,y)
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def line(x1, y1, x2, y2):
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jumpto(x1, y1)
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pendown()
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goto(x2, y2)
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def coosys():
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line(-1, 0, N+1, 0)
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line(0, -0.1, 0, 1.1)
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def plot(fun, start, color):
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pencolor(color)
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x = start
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jumpto(0, x)
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pendown()
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dot(5)
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for i in range(N):
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x=fun(x)
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goto(i+1,x)
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dot(5)
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def main():
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reset()
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setworldcoordinates(-1.0,-0.1, N+1, 1.1)
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speed(0)
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hideturtle()
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coosys()
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plot(f, 0.35, "blue")
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plot(g, 0.35, "green")
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plot(h, 0.35, "red")
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# Now zoom in:
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for s in range(100):
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setworldcoordinates(0.5*s,-0.1, N+1, 1.1)
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return "Done!"
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if __name__ == "__main__":
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main()
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mainloop()
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