1. Functions and Expressions
Note to Instructor: Slides may be used either in a traditional lecture format or with an Active Learning approach. If you are using an active learning approach, suggestions will appear in this "Notes" area on appropriate slides.

2. What will we learn today?
We will learn today
What are functions and expressions
Functions in real life
Built-in functions in Alice
How to use functions and expressions

3. Functions and Expressions
A statement you can use to ask a question about conditions/properties of an object or to compute a value
Expression
A math operation on numbers or other kinds of values

4. Functions in Real-Life
We use functions to compute the hours in any given number of days (hours=days*24)
The vending machine; you insert a currency into the machine and it dispenses items such as snacks, chocolates, water..etc to you automatically

5. Functions We use functions to get the information we need
Q:How far away the camel is from the palm trees??

6. Built-in Functions
Alice system provides a set of built-in functions for each object
To view a list of built-in functions associate with an object in a world
Select the object in the object tree
View the functions in the details area

7. Built-in Functions
The Built-in functions are divided into subcategories
Proximity: how close the object is to other objects e.g. distance to
Size: dimensions e.g. height, width and depth
Spatial relation: orientation compared to other objects in the world e.g. to right of
Point of view: position in the world
Other: miscellaneous items

8. Expressions Alice Provides math operators for common math expressions
Add(+), subtract(-), multiply (*) and divide(/)
Obtaining math expression

9. Camel and distance to tree example
We want the camel to move towards the palm tree and stops there
Select the camel from the object tree
Click on the methods tab
Drag the ‘move’ method and place it into the program code editor (the large yellow pane)

10. Camel and distance to tree example
Choose forward and 1m from the list shown
Select the functions tab and drag the ‘distance to’ function under ‘proximity’ into the ‘1 meter’ box

11. Camel and distance to tree example
Choose ‘plamTree’ from the list and the ‘entire plamTree’

12. Camel and distance to tree example
Click on the arrow as shown below and choose math, camel distance to palmTree-1

13. Camel and distance to tree Simulation

14. Let’s work with Alice
We will take the “raceCar” simulation and make the car
Move to the palmTree
Turn to face the lampPost
Move forward half the distance to the lampPost