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3. Text
To print the word "house", if you write
print house
LOGO sees the word "house" as a command. To enable LOGO to treat the
word "house" as text, there must be double quote marks placed immediately
before and after it.
print "house"
4. Variable name
Placing a colon ":" before a word enables LOGO to read the word as a variable.
In the example above, "forward :n" causes LOGO to read ":n" as a variable
and use it as input to the command "forward."
1. Drawing Commands
forward
(fd)
back
(bk)
left
(lt)
right
(rt)
setx
sety
setxy
setheading
(seth) n
setpc
setbg
pencolour
(pc)
background
(bg)
penup
(pu)
pendown
(pd)
showturtle
(st)
hideturtle
(ht)
home
It should be written as
n
turtle goes forward N steps.
n
turtle goes back N steps.
n
rotate the turtle left (counterclockwise) N degrees.
n
rotate the turtle right (clockwise) N degrees.
n
turtle goes to X = N coordinate.
n
turtle goes to Y = N coordinate.
x y
turtle goes to (x,y) coordinate.
turn the turtle N degrees (clockwise) from the straight
up position.
n
set pen colour to N(N = 0~3). (0=white,
1=lightgrey, 2=dark grey, 3=black).
n
set background colour to N(N = 0~3). (0=white,
1=lightgrey, 2=dark grey, 3=black).
get current colour N of pen(N=0~3). (0=white,1=lightgrey,
2=dark grey, 3=black).
get current background colour N (N=0~3).(0=white,
1=lightgrey, 2=dark grey, 3=black).
put the turtle's pen up. When the turtle moves, it
does not draw a line.
put the turtle's pen down and draws a line when the
turtle moves.(default status)
make the turtle shape visible.(default status)
make the turtle shape invisible.
move the turtle to the centre of the screen, points
the turtle straight up (HEADING 0), but does not clear
the graphics screen or alter the pen state.
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