Logo Programming

INSTRUCTION MEANING FORWARD n Move n mm forward BACKWARD n Move n mm backward LEFT t Turn left t degrees RIGHT t Turn right t degrees REPEAT n Repeat the following instructions n times END REPEAT Finish the REPEAT loop

For a regular closed shape: Pendown (to ensure the pen is down so that a line is made when you move) Note you can sometimes get away with assuming the pen is down or up already before you start. Right / Left 90 (usually to face along one of the sides) Repeat .... (the number of sides) Forward .... (the length of each side) Right 360/.... (the number of sides) End Repeat

Example - for a octagon: Pendown Note you can sometimes get away with assuming the pen is down or up already before you start. Right 90 Repeat 8 Forward 100 Right 45 (360/8) End Repeat

To complete a irregular unclosed path: Just use successive Penup/Pendown, Right / Left & Forward commands to complete the path.

Example of a irregular unclosed path: PEN UP Note you can sometimes get away with assuming the pen is down or up already before you start. FORWARD 50 RIGHT 90 PENDOWN FORWARD 70 PENUP FORWARD 40 FORWARD 80

Example to complete two regular shapes: Use a Backward command in between the first and second shapes. Note that there many ways of doing this PEN DOWN LEFT 90 REPEAT 5 FORWARD 50 RIGHT 72 END REPEAT PENUP BACKWARD 140 PENDOWN REPEAT 4 FORWARD 60 RIGHT 90 END REPEAT PEN DOWN LEFT 90 REPEAT 5 FORWARD 50 RIGHT 72 END REPEAT PENUP BACKWARD 80 RIGHT 90 PENDOWN REPEAT 4 FORWARD 60 RIGHT 90 END REPEAT OR Note that there many ways of doing this but questions may force you to do it one particular way by making you fill out blanks rather than letting you decide from scratch.

Websites to use to find out more / “play around” with Logo. Math Playground Logo Controlling Things On the screen (igcseict.info) BBC Bitesize Logo But note that you are forced, in this website, to assume that the pen is already up before you start.