Alice in Action with Java

1
Alice in Action with Java

• Chapter 5
• Random Numbers

2
Random Numbers

• Certain kinds of applications need random numbers
• simulations
• games
• encryption utilities use random numbers to create
  a code for scrambling the data being encrypted
• programs that test other programs sometimes
  generate random sets of data

3
Random Numbers in Alice

• The world has two functions
• random number
• by default the function returns a number between
  0 and 1
• You can tell the function to use a different
  range by selecting more and then fill in the
  minimum and maximum values
• You can also specify integers only
• choose true x of the time

4
Random Motion

• You could make an alice object move a random
  distance in a random direction with a
• do together
• move forward/backwards by a random amount
• move up/down by a random amount
• move left/right by a random amount

5
Choose true

• If you have an action that needs to happen some
  percentage of the time there is a world function
  to use
• Select choose true from the world's methods
• select a per cent value