logo for beginners

Logo for BeginnersBy Chris 9S

What are control systems A control system uses microprocessors

to control physical conditions. This is used for:

Air condition Central Heating Medical Applications Car Manufacture plants Process Control

Physical Conditions (or variables) that are controlled by microprocessors are: Temperature Pressure Humidity Light Moisture

What is Logo? Logo is a simulation of a control system It uses a triangular turtle shape as its

cursor It is a program developed by MIT

(Massachusetts Institute of Technology)

Some Basic Commands fd= moves turtle forward e.g. fd 40 bk= moves turtle backward e.g. bk 50 rt= rotates turtle right e.g. rt 70 lt= rotates turtle left e.g. lt 90 pu= pen up pd= pen down

How to make a square? fd 80 rt 90 fd 80 rt 90 fd 80 rt 90 fd 80 rt 90orrepeat 4 [fd 80 rt 90]

Repeat Command The repeat command is used when you

want to repeat a structure commands again and again e.g. any polygon

To use ‘repeat’ in logo, you need to know by what angle you need to turn the turtle.

You would need to do 360/(number of sides).

E.g. Hexagon angle= 360/6= 60

This means that you would do type in: repeat 6 [fd 80 rt 60] Note: don’t use these brackets: () and

{} Always use this bracket: []

How to draw a circle To draw a circle, you would type: repeat 360 [fd 1 rt 1]

Procedures A procedure is a single command that

you would type in the command box and it will produce a series of commands to produce a drawing e.g. “house”

Sub-routine A sub-routine is a series of commands

that you would put in the procedure e.g. circle

The following sub-routines were used to build the house

Small Circle for the knob

Pentagon for the house door

Square for body of house

Triangle for roof

+ + + =

Variables A Variable is a numeric data that can be

keep on changing e.g. numerical data in a cell in Microsoft Excel.

Variables are useful when they are more or less amount of numbers appear e.g. clients in a cliental list

Variables in MSWLOGO When using the repeat command in LOGO,

you can change the length of the square without having to keep going to Edall and changing the length

Ex. If you would want to do a square, copu into edall: To square :length repeat 4 [fd :length rt 90] end

To make the square of length 100 you insert “square 100” in the command box

Where to get MSWLOGO This Website:

http://mswlogo.en.softonic.com/ Its free and virus-free!