Python reference

General Python

def <func_name>():
    <statement>
    <statement>
 Define a function (named group of statements) with name func_name containing indented statements. 
def draw_square():
    for i in range(4):
        forward(100)
        right(90)

Defines the draw_square() function. Notice that this won’t do anything because the function hasn’t been called!

 
<func_name>()
 Call the function named func_name defined previously. 
draw_square()

Runs the code written above for drawing a square.

 
def <func_name>(<param1>, <param2>...):
    <statement>
    <statement>
 Define a function (named group of statements) with name func_name and parameters param1, param2 containing indented statements. Parameters provide additional information to the function to provide greater flexibility. 
def draw_square(size):
    for i in range(4):
        forward(size)
        right(90)

Defines the draw_square(size) function. Notice that when the user calls this, a number must be in the parentheses. For example, a call on draw_square(30) will result in a square of side 30.

Loops

for i in range(<num>):
    <statement>
    <statement>
 Repeats indented statements <num> times. 
for i in range(4):
    forward(100)
    right(90)

Draws a square with a side of 100.

Turtle Graphics (requires from turtle import * at top of program)

forward(<pixels>)

fd(<pixels)

 Move the turtle forward by the specified number of pixels in the current orientation. forward(100)

Moves the turtle forward by 100 pixels
backward(<pixels>)

bk(<pixels)

 Move the turtle backward by the specified number of pixels in the current orientation backward(100)

Moves the turtle backward by 100 pixels
left(<angle>)

lt(<angle>)

 Turn the turtle left by the specified number of degrees left(90)

Turns the turtle left 90 degrees
right(<angle>)

rt(<angle>)

 Turn the turtle right by the specified number of degrees right(90)

Turns the turtle right 90 degrees
up() Bring the pen up (moving the turtle doesn’t draw on the canvas) up()

goto(0, 0)

Return to origin without leaving a trace.
down() Bring the pen down (moving the turtle draws on the canvas)
circle(<radius>) Draw a circle of the given radius circle(30)
Draw a circle of radius 30.
hideturtle() Hide the turtle.
goto(<x>, <y>) Move the turtle to the specified location. goto(0, 0)

down()

goto(100, 100)

Draw a line between the origin and the point (100, 100)
color(<str>)

color(<red>, <green>, <blue>)

 Change the drawing color according to either a string (color name or hex color code starting with #) or red, green blue values between 0 and 1. color(“red”)

Makes the pen color red.

color(1, 0, 1)

Make the pen color purple.
bgcolor(<str>) Change the canvas’ background color according to the same rules as color. bgcolor(“red”)

Makes the background color red.
fill(<boolean>) Change the fill status.  Call fill(True) before drawing a closed shape to fill and fill(False) at the end. 
color("green")
fill(True)
for i in range(4):
    forward(100)
    right(90)
fill(False)

Draw a green filled square.
shape(<shape>) Change the turtle’s appearance.  By default, the following shapes are available: “arrow”, “turtle”, “circle”, “square”, “triangle”, “classic” shape(“turtle”)

Changes the shape of the turtle to look like a turtle.
register_shape(<file>) Add a GIF image as a possible turtle.  Must be in the same directory. register_shape(“cake.gif”)

shape(“cake.gif”)

Adds a cake image to the list of possible turtles and sets the turtle to look like a cake.
stamp() Draw an impression of the turtle.