Logo Tutorial : Learn LOGO language

Logo Tutorial

logo language

Learn LOGO language

LOGO is a computer programming language used for functional programming

About Logo:
Logo is a language to do draw and limited mathematical calculation. This is manly used to developed commuter interest ,language skill, under stand  in a new computer user / child. This language primary purpose was to teach children to familiar with computer programming.

History:
Logo was developed in the late 1960s at Bolt Beranek and Newman, Inc., in Cambridge, MA by W. Feurzeig, D. Bobrow and S. Papert.

Language Important command :

cs - clear screen
control +c  to stop a loop process.
bye - exit from logo.

Drawing Commands
The simple Logo drawing commands move the turtle forward and backward and turn it right or left. The commands and their abbreviations are given below:

fd move forward
bk move backward
rt move right
lt move left

No try this :

fd 60 rt 120 fd 60 rt 120 fd 60 rt 120

to save time the above command we will write as

repeat 3 [fd 60 rt 120]

The square brackets indicate that the enclosed commands are to be executed three times.

Logo has a number of other drawing commands, including those shown below.

pu penup

The pendown and penup commands tell the turtle to leave ink on the screen as it moves or not leave ink, respectively.

ht hideturtle
st showturtle

The hideturtle and showturtle commands hide or show the turtle but do not affect its ability to leave ink as it moves.

home

The home command causes the turtle to return to the center of the screen.

label

The label command takes a single word as a quoted string (e.g. ``a_string) or a list of words in [] brackets without quotation (e.g. [a string of letters]) and prints them on the graphics window at the location of the turtle. (Try them!)

setxy

The command setxy takes two arguments, treats the first as the value of the abscissa (horizontal axis) and the second as a value of the ordinate (vertical axis). It places the turtle at these coordinates, possibly leaving ink as it does so.

Now try and see What kind of figure does the following command sequence produce?

cs pu setxy -60 60 pd home rt 45 fd 85 lt 135 fd 120