plotting slows down

[Norman Elliott]

On Monday, 13 January 2014 08:15:08 UTC, Norman Elliott  wrote:
> First let me say I have not done much python programming!
> 
> I am running Python 2.7.3.
> 
> I am trying to use python as a front end to a simple oscilloscope.
> 
> Ultimately I intend to use it with my micropython board.
> 
> 
> 
> At the moment I am just developing it. All it does is use a module I found called graphics.py to create a window and display randomly generated data.
> 
> 
> 
> Each time it goes through the outer loop it gets slower and slower.
> 
> I put in a small delay just so I could observe what is happening and for the first line it draws it takes about a second. If I set it to loop 20 times the final loop takes more than 6 seconds.
> 
> Can anyone explain what I am doing wrong please?
> 
> Here is the code:
> 
> [code]
> 
> #!/usr/bin/python
> 
> from graphics import *
> 
> import random
> 
> import time
> 
> 
> 
> xpos=1200
> 
> ypos=400
> 
> ypnt=ypos/2
> 
> pos=1
> 
> #setBackground("white")
> 
> def main():
> 
> 	win = GraphWin("My Circle", xpos, ypos)
> 
> #	win.setBackGround('white')
> 
> 	for y in range(1,5):
> 
> 		cir2 = Circle(Point(xpos/2,20), 10)
> 
> 		cir2.setFill("white")
> 
> 		cir2.draw(win)
> 
> 		message = Text(Point(win.getWidth()/2, 20), y)
> 
> 		message.draw(win)
> 
> 		j = random.randint(1,ypos)
> 
> 		for x in range(1,xpos):
> 
> 			updown = random.randint(0,1)
> 
> 			if updown:
> 
> 				j=j+1
> 
> 			else:
> 
> 				j=j-1
> 
> 			if j <1:
> 
> 				j=ypos/2
> 
> 			if j>ypos-1:
> 
> 				j=ypos/2
> 
> 			win.plot(x,j,"red")
> 
> 			time.sleep(.0001)
> 
> 
> 
> main()
> 
> time.sleep(5)
> 
> [/code]

Okay, maybe I misunderstood what it was doing. I have checked and I will do a find and replace of the tabs with 4 spaces in future.