FM / turtledemo

/usr/lib64/python3.8/turtledemo

Name	Size	Mode	Actions
__pycache__/	-	0755	rm
bytedesign.py	4247	0755	edit dl rm
chaos.py	951	0644	edit dl rm
clock.py	3200	0755	edit dl rm
colormixer.py	1339	0644	edit dl rm
forest.py	2965	0755	edit dl rm
fractalcurves.py	3472	0755	edit dl rm
lindenmayer.py	2433	0755	edit dl rm
minimal_hanoi.py	2050	0755	edit dl rm
nim.py	6513	0644	edit dl rm
paint.py	1290	0755	edit dl rm
peace.py	1065	0755	edit dl rm
penrose.py	3379	0755	edit dl rm
planet_and_moon.py	2824	0755	edit dl rm
rosette.py	1361	0644	edit dl rm
round_dance.py	1804	0644	edit dl rm
sorting_animate.py	5029	0644	edit dl rm
tree.py	1400	0755	edit dl rm
turtle.cfg	160	0644	edit dl rm
two_canvases.py	1119	0644	edit dl rm
yinyang.py	820	0755	edit dl rm
__init__.py	314	0644	edit dl rm
__main__.py	14241	0644	edit dl rm

Edit: /usr/lib64/python3.8/turtledemo/planet_and_moon.py (2824B)

#! /usr/bin/python3.8
"""       turtle-example-suite:

tdemo_planets_and_moon.py

Gravitational system simulation using the
approximation method from Feynman-lectures,
p.9-8, using turtlegraphics.

Example: heavy central body, light planet,
very light moon!
Planet has a circular orbit, moon a stable
orbit around the planet.

You can hold the movement temporarily by
pressing the left mouse button with the
mouse over the scrollbar of the canvas.

"""
from turtle import Shape, Turtle, mainloop, Vec2D as Vec

G = 8

class GravSys(object):
    def __init__(self):
        self.planets = []
        self.t = 0
        self.dt = 0.01
    def init(self):
        for p in self.planets:
            p.init()
    def start(self):
        for i in range(10000):
            self.t += self.dt
            for p in self.planets:
                p.step()

class Star(Turtle):
    def __init__(self, m, x, v, gravSys, shape):
        Turtle.__init__(self, shape=shape)
        self.penup()
        self.m = m
        self.setpos(x)
        self.v = v
        gravSys.planets.append(self)
        self.gravSys = gravSys
        self.resizemode("user")
        self.pendown()
    def init(self):
        dt = self.gravSys.dt
        self.a = self.acc()
        self.v = self.v + 0.5*dt*self.a
    def acc(self):
        a = Vec(0,0)
        for planet in self.gravSys.planets:
            if planet != self:
                v = planet.pos()-self.pos()
                a += (G*planet.m/abs(v)**3)*v
        return a
    def step(self):
        dt = self.gravSys.dt
        self.setpos(self.pos() + dt*self.v)
        if self.gravSys.planets.index(self) != 0:
            self.setheading(self.towards(self.gravSys.planets[0]))
        self.a = self.acc()
        self.v = self.v + dt*self.a

## create compound yellow/blue turtleshape for planets

def main():
    s = Turtle()
    s.reset()
    s.getscreen().tracer(0,0)
    s.ht()
    s.pu()
    s.fd(6)
    s.lt(90)
    s.begin_poly()
    s.circle(6, 180)
    s.end_poly()
    m1 = s.get_poly()
    s.begin_poly()
    s.circle(6,180)
    s.end_poly()
    m2 = s.get_poly()

planetshape = Shape("compound")
    planetshape.addcomponent(m1,"orange")
    planetshape.addcomponent(m2,"blue")
    s.getscreen().register_shape("planet", planetshape)
    s.getscreen().tracer(1,0)

## setup gravitational system
    gs = GravSys()
    sun = Star(1000000, Vec(0,0), Vec(0,-2.5), gs, "circle")
    sun.color("yellow")
    sun.shapesize(1.8)
    sun.pu()
    earth = Star(12500, Vec(210,0), Vec(0,195), gs, "planet")
    earth.pencolor("green")
    earth.shapesize(0.8)
    moon = Star(1, Vec(220,0), Vec(0,295), gs, "planet")
    moon.pencolor("blue")
    moon.shapesize(0.5)
    gs.init()
    gs.start()
    return "Done!"

if __name__ == '__main__':
    main()
    mainloop()

#! /usr/bin/python3.8 """ turtle-example-suite: tdemo_planets_and_moon.py Gravitational system simulation using the approximation method from Feynman-lectures, p.9-8, using turtlegraphics. Example: heavy central body, light planet, very light moon! Planet has a circular orbit, moon a stable orbit around the planet. You can hold the movement temporarily by pressing the left mouse button with the mouse over the scrollbar of the canvas. """ from turtle import Shape, Turtle, mainloop, Vec2D as Vec G = 8 class GravSys(object): def __init__(self): self.planets = [] self.t = 0 self.dt = 0.01 def init(self): for p in self.planets: p.init() def start(self): for i in range(10000): self.t += self.dt for p in self.planets: p.step() class Star(Turtle): def __init__(self, m, x, v, gravSys, shape): Turtle.__init__(self, shape=shape) self.penup() self.m = m self.setpos(x) self.v = v gravSys.planets.append(self) self.gravSys = gravSys self.resizemode("user") self.pendown() def init(self): dt = self.gravSys.dt self.a = self.acc() self.v = self.v + 0.5*dt*self.a def acc(self): a = Vec(0,0) for planet in self.gravSys.planets: if planet != self: v = planet.pos()-self.pos() a += (G*planet.m/abs(v)**3)*v return a def step(self): dt = self.gravSys.dt self.setpos(self.pos() + dt*self.v) if self.gravSys.planets.index(self) != 0: self.setheading(self.towards(self.gravSys.planets[0])) self.a = self.acc() self.v = self.v + dt*self.a ## create compound yellow/blue turtleshape for planets def main(): s = Turtle() s.reset() s.getscreen().tracer(0,0) s.ht() s.pu() s.fd(6) s.lt(90) s.begin_poly() s.circle(6, 180) s.end_poly() m1 = s.get_poly() s.begin_poly() s.circle(6,180) s.end_poly() m2 = s.get_poly() planetshape = Shape("compound") planetshape.addcomponent(m1,"orange") planetshape.addcomponent(m2,"blue") s.getscreen().register_shape("planet", planetshape) s.getscreen().tracer(1,0) ## setup gravitational system gs = GravSys() sun = Star(1000000, Vec(0,0), Vec(0,-2.5), gs, "circle") sun.color("yellow") sun.shapesize(1.8) sun.pu() earth = Star(12500, Vec(210,0), Vec(0,195), gs, "planet") earth.pencolor("green") earth.shapesize(0.8) moon = Star(1, Vec(220,0), Vec(0,295), gs, "planet") moon.pencolor("blue") moon.shapesize(0.5) gs.init() gs.start() return "Done!" if __name__ == '__main__': main() mainloop()