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requires them. Disable executable bits and shebang lines in test and benchmark files in order to prevent using a random system python, and in source files of modules which don't provide command line interface. Fixed shebang line to use python3 executable in the unittestgui script.
119 lines
2.4 KiB
Python
Executable file
119 lines
2.4 KiB
Python
Executable file
#!/usr/bin/env python3
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""" turtle-example-suite:
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xtx_lindenmayer_indian.py
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Each morning women in Tamil Nadu, in southern
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India, place designs, created by using rice
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flour and known as kolam on the thresholds of
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their homes.
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These can be described by Lindenmayer systems,
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which can easily be implemented with turtle
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graphics and Python.
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Two examples are shown here:
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(1) the snake kolam
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(2) anklets of Krishna
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Taken from Marcia Ascher: Mathematics
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Elsewhere, An Exploration of Ideas Across
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Cultures
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"""
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################################
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# Mini Lindenmayer tool
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###############################
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from turtle import *
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def replace( seq, replacementRules, n ):
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for i in range(n):
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newseq = ""
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for element in seq:
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newseq = newseq + replacementRules.get(element,element)
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seq = newseq
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return seq
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def draw( commands, rules ):
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for b in commands:
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try:
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rules[b]()
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except TypeError:
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try:
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draw(rules[b], rules)
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except:
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pass
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def main():
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################################
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# Example 1: Snake kolam
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################################
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def r():
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right(45)
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def l():
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left(45)
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def f():
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forward(7.5)
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snake_rules = {"-":r, "+":l, "f":f, "b":"f+f+f--f--f+f+f"}
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snake_replacementRules = {"b": "b+f+b--f--b+f+b"}
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snake_start = "b--f--b--f"
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drawing = replace(snake_start, snake_replacementRules, 3)
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reset()
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speed(3)
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tracer(1,0)
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ht()
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up()
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backward(195)
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down()
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draw(drawing, snake_rules)
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from time import sleep
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sleep(3)
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################################
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# Example 2: Anklets of Krishna
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################################
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def A():
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color("red")
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circle(10,90)
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def B():
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from math import sqrt
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color("black")
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l = 5/sqrt(2)
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forward(l)
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circle(l, 270)
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forward(l)
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def F():
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color("green")
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forward(10)
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krishna_rules = {"a":A, "b":B, "f":F}
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krishna_replacementRules = {"a" : "afbfa", "b" : "afbfbfbfa" }
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krishna_start = "fbfbfbfb"
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reset()
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speed(0)
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tracer(3,0)
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ht()
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left(45)
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drawing = replace(krishna_start, krishna_replacementRules, 3)
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draw(drawing, krishna_rules)
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tracer(1)
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return "Done!"
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if __name__=='__main__':
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msg = main()
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print(msg)
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mainloop()
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