LOGO is a powerful graphics tool that is free to download and easy to use. Throughout the remainder of your time at Folsom, you will be learning to use LOGO for different purposes.
Getting Started
Part 1. Download and installation
You can download logo from this website: http://www.softronix.com/logo.html
Then, double click on it and it should install itself.
Finally, select MSWLogo from the start menu on your computer and launch LOGO.
Part 2. Initial Commands
Part 3. Initial Programs
Part 4. Input Based Programs
Part 5. Inputs and Loops Programs
Part 6. Programs to solve problems
Part 7. LOGO and Music
Part 2.
Getting Familiar with LOGO
Logo will launch by showing you a couple of pop up windows. Just close the windows and the program will launch.
Once the program has launched, you should see a split screen. On the top of the split screen, you should see a triangle. Most LOGO books call this triangle the turtle. This is a long story and I will explain it to you in class if you like.
You type commands into the white window at the bottom of the screen. Type the following commands and record what happens:
Command |
Result |
Forward 10 |
|
Forward 100 |
|
Forward 1000 |
What is the forward for?
What is the number for?
Now that you have learned a simple command, let’s learn another. Type CS into the window and record what happens:
Command |
Result |
CS |
Now, you can learn to guess a little about how logo works. Type the following commands but make a prediction before you press return. After you enter the command, record what happens.
Command |
Prediction |
Result |
Back 10 |
||
Back 100 |
||
Back 1000 |
Now that you have learned about forward and back, you can learn a little about turning. Type the following commands and see what happens:
Command |
Result |
Rt 90 forward 10 |
|
Rt 90 forward 10 |
What did the Rt do?
What did the 90 do?
Now, clear the screen and complete this chart. Don’t forget to make some predictions.
Command |
Prediction |
Result |
Lt 90 forward 10 |
||
Lt 90 forward 10 |
||
Lt 90 forward 10 |
||
Lt 90 forward 10 |
So far, you have been doing a superb job of learning to make the turtle go places and you have even learned to draw a square.
Now, you need to learn a little more about angles and how the turtle understandings angles.
Complete the following commands and make some predictions about the shape you will draw.
Command |
Prediction |
Result |
Forward 60 rt 60 |
||
Forward 60 rt 60 |
||
Forward 60 rt 60 |
What happened?
Should you have drawn a triangle? Remember, an equiangular triangle has angles of 60 degrees. Isn’t that what you told the turtle to do?
For homework, see if you can explain the turtle’s strange behavior.
Day 2.
You should have learned that the angle the turtle makes is based on the center of the turtle, and not the bottom of the screen. This means that if you rt 90, you turn to the right. However, if you rt 45, you turn halfway toward the right. If you rt 60, you turn 2/3 of the way toward the rt. However, a triangle angle might be 60 degrees, but they are actually more than that if you have to physcially turn to make the angle.
Experiment 1.
Step 1
Make a circle on piece of paper and mark 0, 30, 60, 90, 120, 150, 180 degrees on the sheet.
Make a triangle, with each side 1 meter, that has 3 equal angles on the floor using tape.
Step2
Trace the steps of your triangle and record the angle you would have to turn at each turn to make your angle.
Necessary Angle |
|
Turn 1 |
|
Turn 2 |
|
Turn 3 |
What pattern did you discover?
You should have discovered that the inside angle is what you measure but the turtle makes the outside angle. This means the turtle needs to turn 180-angle degrees to make the turn you want it to make. This is the difference between an interior and an exterior angle.
Try to type the following:
Rt 120 forward 10
Rt 120 forward 10
Rt 120 forward 10
What shape does this make?
Why does it work?
Fill in this table and explain how it would work?
Commands to make a triangle in logo |
||
Interior Angle |
Exterior Angle |
Command |
45 |
Rt forward 10 |
|
45 |
Rt forward 10 |
|
90 |
Rt forward 10 |
New Command
Type the following into the screen and predict what will happen:
Command |
Prediction |
Results |
Repeat 2[forward 10 rt 90] |
||
Repeat 3[forward 10 rt 90] |
What command would enable you to draw a square?
Homework:
Can you write a command that will make an equilateral, equiangular triangle?
Answer
Repeat 3[forward 10 rt 130]
Part III Writing Programs
Today you will learn to write your first logo programs. A program is a saved list of commands.
To learn more about programs, click on the edall feature on the right hand side of the screen.
Type the following into the window:
to triangle
repeat 3[forward 100 rt 130]
end
When you have finished, select the save and exit function from the file tab at the top of the screen.
In the command window, type triangle
You should now see the results of the repeat 3[forward 100 rt 130]. When you type, triangle, everything between the to triangle and the end is executed.
Clear the screen and try this command.
Command |
Prediction |
Result |
Repeat 4[triangle] |
What happened?
Write a program that will make other shapes:
Rhombus
Trapezoid
Parallelogram
Pentagon
Hexagon
Octagon
Part IV Writing Programs with Inputs
Open the triangle program using the File Load command. Now, make a slight change.
to triangle :n
repeat 3[forward :n rt 130]
end
Now, save and exit the screen.
Now, enter the following command and record what happens:
Command |
Prediction |
Results |
Triangle 10 |
||
Triangle 25 |
||
Triangle 100 |
Try to write a program that will make a square of any size.
Now, revise all of the programs you have already written to make a shape of any given size:
Rhombus
Trapezoid
Parallelogram
Pentagon
Hexagon
Octagon
http://www.math.utah.edu/~clemens/relearning.html
Rhombus Program rt 45 forward 25 rt 45 forward 25 rt 135 forward 25 rt 45 forward 25 |
To Rhombus Repeat 4[rt 45 forward 25] End |
To Rhombus :n Repeat 4[rt 45 forward :n] End |
Trapezoid program rt 45 forward 25 rt 45 forward 25 rt 45 forward 25 rt 135 forward 61 |
To Trapezoid Repeat 3[rt 45 forward 25] Rt 135 forward 61 End |
|
Parallelogram rt 45 forward 25 rt 45 forward 30 rt 135 forward 25 rt 45 forward 30 |
To Parallelogram rt 45 forward 25 rt 45 forward 30 rt 135 forward 25 rt 45 forward 30 end |
|
Pentagon Rt 72 forward 25 Rt 72 forward 25 Rt 72 forward 25 Rt 72 forward 25 Rt 72 forward 25 |
To Pentagon Repeat 5[rt 72 forward 25] End |
To Pentagon :n Repeat 5[rt 72 forward n] End |
Hexagon Rt 60 forward 25 Rt 60 forward 25 Rt 60 forward 25 Rt 60 forward 25 Rt 60 forward 25 Rt 60 forward 25 |
To Hexagon Repeat 6[rt 60 forward 25] End |
To Hexagon :n Repeat 6[rt 60 forward :n] End |
Octagon Rt 45 forward 25 Rt 45 forward 25 Rt 45 forward 25 Rt 45 forward 25 Rt 45 forward 25 Rt 45 forward 25 Rt 45 forward 25 Rt 45 forward 25 |
To Octagon Repeat 8 [rt 45 forward 25] End |
To Octagon Repeat 8 [rt 45 forward :n] End |
Advanced Topics
Write a program to draw an equilateral polygon of any number of sides:
to polygon :s :t
cs
repeat :s[forward :t rt 180-(((:s-2)*180)/:s)]
end
Using Advanced Concepts like Loops to make spirals
to spiral :size
if :size > 30 [stop] ; a condition stop
fd :size rt 15 ; many lines of action
spiral :size *1.02 ; the tailend recursive call
end