# 14.1. Turtle Functions and Procedures¶

Learning Objectives:

• Introduce more turtle functions and procedures.

• Show examples using conditionals with turtles.

• Use the modulo operator to detect odd and even

• Show how to generate random numbers in Python

• Use conditionals to avoid a collision

Turtles can do more than go forward, turn left, and turn right. The table below lists turtle functions and procedures.

Name

Parameters

Description

backward

amount

Moves the turle backward by the specified amount

color

colorname

Sets the color for drawing. Use ‘red’, ‘black’, etc

forward

amount

Moves the turtle forward by the specified amount

goto

x,y

Moves the turtle to position x,y

left

angle

Turns the turtle counter clockwise by the specified angle

pendown

None

Puts down the turtles tail so that it draws when it moves

penup

None

Picks up the turtles tail so that it doesn’t draw when it moves

pensize

width

Sets the width of the pen for drawing

right

angle

Turns the turtle clockwise by the specified angle

angle

Turns the turtle to face the given heading. East is 0, north is 90, west is 180, and south is 270.

shape

shapename

Should be ‘arrow’, ‘classic’, ‘turtle’, or ‘circle’

stamp

None

Leaves an impression of a turtle shape at the current location

Turtle

None

Creates and returns a new turtle object

xcor

None

Returns the x value of the turtle’s position

ycor

None

Returns the y values of the turtle’s position

Once you are comfortable with the basics of turtle graphics you can read about even more options on the Python Docs Website.

Note

Discuss topics in this section with classmates.