MSW Logo-for beginners

In this post, I would like to write about MSW Logo. This is a programming tool for beginners like me.

LOGO stands for Language of Graphics Oriented. It is specially created programming language so that we can have fun and learn the art of the programming. With Logo we can draw, design and perform calculation.

How to go to logo?

Windows 7

Click Start—->All Program—->MSW Logo.

Windows 10

Click Windows button—->Type MSW Logo—->Click MSW Logo.

What is a turtle?

A turtle is a triangle which draws on the Logo Graphics Window according the Logo commands those we enter. The centre of the Graphics screen is the home of the Turtle.

These commands are also known as Primitives. Primitive are entered in the bar called Command Input Box.

The basic logo Primitives are shown below.

Primitives	Meaning	Action
FD	FORWARD	To move the turtle forward.
BK	BACK	To move the turtle backwards.
RT	RIGHT	To move the turtle to the right.
LT	LEFT	To move the turtle to the left.
HT	HIDE TURTLE	To hide the turtle.
ST	SHOW TURTLE	To show the turtle.
CS	CLEAR SCREEN	To clear the screen and send the turtle to the Home position.
CT	CLEAR TEXT	To clear all the commands in the Recall list box.
SETH		To rotate the turtle to its orginal positon.
HOME		To bring the turtle to its Home position.
PRINT		To write.
SUM		To add two numbers.
BYE		The shortcut primitive to exit from logo.
DIFFERENCE		To subract one number to another.
PRODUCT		To multiply to number.
QUOTIENT		To display the quotient of two numbers.
REMAINDER		To display the remainder of two numbers.
CLEAN		To erase all graphics in the graphics window.

PENUP or PU Primitive

Use the PENUP (PU) to lift the turtle’s pen. After you have given the PU primitive, the turtle moves without line.

PENDOWN or PD Primitive

Use the PENDWN (PD) after the PENUP primitive. It puts the pen down,and starts drawing again.

Example

FD 40 – The turtle draw a line of 40 steps.

PU – The pen is lifted.

FD 40 – The turtle moves up 40 steps without drawing.

PD – The turtle’s pen is down.

FD 20 – The turtle draw a line of 20 steps.

All commands given in LOGO must be followed by the key “Enter”.

PENERASE or PE Primitive

Penerase (PE) is a primitive that act like an eraser.

Example
FD 50 – The turtle moves 50 step forward (FD)
PE – The PENERASE (PE) primitive will be active.
BK 25 – The turtle erases 25 step by moving backward (BK).

SET PEN COLOR or SETPC Primitive

The SET PEN COLOR or SETPC primitive is programmed as to change the color of the turtle’s pen. Colors are represented by numbers given below:

No	Color
0	Black
1	Blue
2	Green
3	Cyan
4	Red
5	Violet
6	Brown
7	Light Gray
8	Dark Grey
9	Light Blue
10	Light Green
11	Light Cyan
12	Light Red
13	Magenta
14	Yellow
15	White

Example

REPEAT primitive

Use the REPEAT primitive to make the computer do a certain task repeatedly. The REPEAT primitive saves a lot of time and effort.

Instead of writing the same command again and again we just write the repeat primitive and the number we should repeat. Repeat primitive is used for looping.

Consider this example –

FD 60 RT 90 FD 60 RT 90

FD 60 RT 90 FD 60 RT 90 (Enter)

This will draw a square.

We can type command as below:

REPEAT 4 [FD 60 RT 90] (Enter)

Let us use REPEAT primitive to draw different shape by trying these example.

Drawing a circle using REPEAT primitive

REPEAT 360 [FD 1 RT 1] (Enter)

Drawing a semicircle

REPEAT 180 [FD 1 RT 1] (Enter)

Drawing an arc

REPEAT 90 [FD 1 RT 1] (Enter)

Drawing a pentagon

REPEAT 5 [FD 50 RT 360/5] (Enter)

Drawing an octagon

REPEAT 8 [FD 50 RT 360/8] (Enter)

Drawing a hexagon

REPEAT 6 [FD 50 RT 360/6] (Enter)

Drawing a triangle

REPEAT 3 [FD 50 RT 360/3] (Enter)

Nested REPEAT

When one REPEAT encloses another REPEAT, it is called a nested REPEAT.
Now let us try out nested REPEAT to draw the following shapes.

1. To draw a star

HT REPEAT 25 [REPEAT 5 [FD 210 RT 114]] (Enter)

2.To Draw a fan

REPEAT 6 [REPEAT 3 [FD 90 RT 120 FD 30 RT 90]] (Enter)

More to learn in MSW logo

1. Zoom- To zoom, we should click the zoom button and it will be asking you In, Out, Normal you choose in it will be zoomed.

2. To change the your Pen size- To change the your Pen size you should click the set button and click pensize. You can choose which size you want and click OK.

3. To save- To save, click the file button and click save as. It will ask where to save, you give the location where to save and click where to save.

The end.

Download logo: http://fmslogo.sourceforge.net/

 

 

Advertisements