30 lines
441 B
Plaintext
30 lines
441 B
Plaintext
make "angle 45
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make "L 1
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make "bob 10
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to draw.pendulum
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clearscreen
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seth :angle+180 ; down on screen is 180
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forward :L*100-:bob
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penup
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forward :bob
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pendown
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arc 360 :bob
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end
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make "G 9.80665
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make "dt 1/30
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make "acc 0
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make "vel 0
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to step.pendulum
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make "acc -:G / :L * sin :angle
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make "vel :vel + :acc * :dt
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make "angle :angle + :vel * :dt
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wait :dt*60
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draw.pendulum
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end
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hideturtle
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until [key?] [step.pendulum]
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