Y5 LF Use random code!

Recap

• What is a procedure?
• How do we code a procedure?
• What is a procedure with variables?

New skill

• random 100 = chooses a number between 1 and 50
• So typing “c random 100” draws a c which is between 1 and 100 big
• setpensize rnadom 30 chooses a pen width between 1 and 30
• If you c had two variables, then you could type:
  • c random 100 random 30
• The coordinates on the drawing canvas go from -250 to 250 across and -250 to 250 up and down.  (0,0) is in the middle.
• To make your shape appear in a random place:
  • setxy (-250 + random 500)  (-250 + random 500)

Tasks

1. Open you “c size procedure” file
2. Add the following code to make lots of random c shapes
   1. repeat 100
   2. [
   3. c random 100 random 30
   4. pu
   5. setxy  (-250 + random 500)  (-250 + random 500)
   6. pd
   7. ]
3. ** Put this line inside the repeat to get random colours!
   1. colour [random 255 random 255 random 255]
4. ** Write your own letter procedure with a variable :size instead of fd/bk numbers
5. *** Can you include a :col variable to choose the colour?
6. How else could you use random?  Try these ideas on different files
   1. circle random 100
   2. repeat 100 [fd random 100 rt 90]
   3. repeat 100 [fd random 200 setxy 0 0 rt 5]

See these posts for more ideas and techniques:

• Draw letter rainbows, flowers and shapes
• Stars and shapes 2
• Stars and shapes 1
• The power of procedures with variables
• Use variables to draw spirals
• Use variables to draw shapes
• Random
• Repeat, setxy, procedures

LOGO example files – can you work out how they work?

• Letter procedures
• Rectangle four variables
• Random colour wheel
• Spiral code
• Another spiral