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+--- Thread: Manipulating code to draw a tree (/thread-21660.html)
Manipulating code to draw a tree - Py_thon - Oct-09-2019
Hi!
I need to manipulate the following code to draw a tree, it currently draws a spiral. I know that the following line needs to be added:
draw_spiral(x2,y2,angle-dangle,dangle,length/dlength,dlength,steps-1,canvas)inside draw spiral. At the end after the first recursive call to draw_spiral.
I just dont see where to add this code, when i add it after the line : draw_spiral(x2,y2,angle+dangle, dangle,length/dlength,dlength,steps-1,canvas) i get the error message unable to alloc 240 bytes.
Where do i need to add the second line above and why do i get the error message?
import tkinter
from math import sin, cos, radians
# DrawWindow - a class for creating a window with a canvas
class DrawingWindow(tkinter.Frame):
def __init__(self):
tkinter.Frame.__init__(self,None)
self.canvas = tkinter.Canvas(self,width=500,height=500,bg='white')
self.canvas.pack(expand=1,anchor=tkinter.CENTER)
self.pack()
def draw_spiral(x,y,angle,dangle,length,dlength,steps,canvas):
# x,y - starting position of the current line segment
# angle - angle of current line segment (0 is straight up)
# dangle - change in angle for each recursion
# length - length of current line segment
# dlength - value to divide length with each step
# steps - number of recursion steps left
# canvas - canvas window to draw on
if steps == 0:
# Bas case -stop here
pass
else:
# Recursive case
# Draw one line segment from (x,y) with the given angle and length
# Calulate end points of this line
x2 = x+sin(radians(angle))*length
y2 = y-cos(radians(angle))*length
# Draw the line on the canvas
canvas.create_line(x,y,x2,y2)
# Recursive call, with end points the drawn lines as new start points,
# with an increase in the angle (turn clockwise)
# and a smaller length, and with step counted down with 1
draw_spiral(x2,y2,angle+dangle, dangle,length/dlength,dlength,steps-1,canvas)
# Create window for drawing on
w = DrawingWindow()
# Draw the spiral on the canvas of that window
# Try to change the parameters and see what happens
draw_spiral(250,250,90,60,100,1.1,35,w.canvas)
# Start the window, so it is displayed
w.mainloop()
RE: Manipulating code to draw a tree - ichabod801 - Oct-09-2019
Please post the full text of your error message.
RE: Manipulating code to draw a tree - Py_thon - Oct-10-2019
The error message is unable to alloc 28 bytes
Process finished with exit code 1073741855
RE: Manipulating code to draw a tree - ichabod801 - Oct-10-2019
That's not a Python error message. How are you running this? The error might be with whatever you are using to run the program.
RE: Manipulating code to draw a tree - Py_thon - Oct-10-2019
I am running pycharm
RE: Manipulating code to draw a tree - ichabod801 - Oct-10-2019
Does it work when you run it from the command line?
RE: Manipulating code to draw a tree - Py_thon - Oct-10-2019
I am sorry but i dont`t know how to run it from the command line, i am new to programming.
RE: Manipulating code to draw a tree - Gribouillis - Oct-11-2019
If you make two recursive calls with steps - 1, it means that starting at level 35 you are attempting to draw 2**34 lines on the canvas. That's more than 17 billion line segments and it may well exhaust some memory resource. Try with 6 steps instead of 35.
RE: Manipulating code to draw a tree - sumana - Nov-21-2019
from turtle import Turtle, mainloop
def tree(plist, l, a, f):
""" plist is list of pens
l is length of branch
a is half of the angle between 2 branches
f is factor by which branch is shortened
from level to level."""
if l > 5:
lst = []
for p in plist:
p.forward(l)
q = p.clone()
p.left(a)
q.right(a)
lst.append(p)
lst.append(q)
tree(lst, l*f, a, f)
def main():
p = Turtle()
p.color("green")
p.pensize(5)
p.speed(100)
p.left(90)
p.penup()
p.goto(0,-200)
p.pendown()
t = tree([p], 200, 65, 0.6)
main()