Instruction manual

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home move the turtle to the center of the screen, points
the turtle straight up (HEADING 0), but does not
clear the graphics screen or alter the pen state.
clearscreen (cs) erase the graphics screen, returns the turtle to the
center of the screen, and sets the turtle’s heading
to 0. CLEARSCREEN does not affect the pen state
or screen colors.
xcor output the X coordinate of the turtle.
ycor output the Y coordinate of the turtle.
heading output the turtle’s degree.
turtlestate (ts) output 4 turtle properties:
pen down?
turtle visible?
background color
pen color
wrap make the turtle remain inside the graphics
window no matter how large a movement
command is given. Any time the turtle moves off
the window borders, it wraps around the window
and reappears on the opposite edge.
window remove the boundaries from the turtle’s field of
movement. If the turtle moves beyond the borders
of the graphics window, it continues to move, but
cannot be seen.
fence prevent the turtle from moving beyond the edge
of the graphics window. If you try to move the
turtle off the window, it does not move and Logo
displays a message.
2. Mathematics Commands
abs n output the absolute value of its input.
arctan n output the arctangent of its input.
cos n output the cosine of its input.
expn n calculate the natural base e (2.71828...) raised to
the power specified by its input.
int n output the integer portion of its input by
removing the decimal portion, if any.
No rounding occurs.
log n output the natural logarithm of its input.
log10 n output the base 10 logarithm of its input.
product m n output the product of its inputs. PRODUCT expects
two inputs, but will accept more if it and all its
inputs are enclosed in parentheses.
quotient m n output the result of dividing the first input by the
second input.