Variables Made Simple

Variables let you store values (like distances, angles, or colors) and reuse them. They make your drawings easier to change.

Using variables for distances and angles 

import turtle

size = 100
angle = 90

t = turtle.Turtle()
t.forward(size)
t.left(angle)
t.forward(size)

Change size and angle at the top and the drawing updates everywhere you used them.

Variables in loops 

import turtle

side = 80
count = 5

t = turtle.Turtle()
for _ in range(count):
    t.forward(side)
    t.left(360 / count)

This uses count to automatically decide how many steps should be taken and what the turning angle should be. Changing count creates a shape with count number of sides.

Naming and simple math

Variables can be updated by expressions. For example, to draw shapes with increasing size:

import turtle

t = turtle.Turtle()
size = 20
for i in range(6):
    t.forward(size)
    t.left(60)
    size = size + 20  # this adds 20 to size, so size will increase each time the turtle moves

Exercises

  • Create variables width and height and draw a rectangle using them.
  • Use a variable to control the number of sides of a polygon, then change the variable to draw different polygons.