Turtle Time!

unexpected observations from a coding exercise

So this article is inspired from a linkedIN post:

Include cool insights...

I was doing some python exercises, looping and iterations and such..

Using a library called ‘Turtle’. It’s a teaching library where you control a little turtle that runs around your screen (as you direct them to)

Leaving their tracks… well… in their tracks.

You send simple commands like: Forward, backward, left, right etc.

Forward and backward move the turtle, while right and left turn it (in degrees)

So my problem was to make a function that could generate a 5-pointed star.

After i solved that, I wanted to make the points variable, so it could generate any number of points.

Here’s the code:

from turtle import *

#This program helps the turtle make a n-pointed star
reset()
shape ('turtle')

def square(sidelength=80, numsides = 5):
    
    #calculate the interior angle that 
    #the turtle must rotate to get 
    #to the next star point
    
    intangle = 360/numsides*2
    
    for i in range(numsides) :
        forward(sidelength)
        right(intangle)

square(numsides=5)

Here’s the results of running it for a 5, 8, and 9 point star…..

So how crazy is that? My code that I thought was awesome, only works on stars with odd numbers of points!

Another crazy thing, since I made it first for a 5-point (odd) star, didn’t “even” (pun intended) think that would be a factor??

The intrinsic conclusion that I came to is that:

My algorithm only works for starts that can be drawn without the pencil leaving the paper!

a 6 points star is basically two offset triangles.

8 points, 2 squares. etc.

I don’t know, I just found it really interesting.

AND I’m also not totally convinced that I can’t tweek it to work for even numbers as well.

Feel free to offer thoughts!!