Alice Programming
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Module 17: Arrays: Working with lists of objects
An array is a list. When you declare an array in Alice, you can select to make it an array.

The variable greeting is not an array, it is a scalar. It has a single value, "Hello World".
When the tortoise says greeting, he says "Hello World"
The variable sayings is an array. The items in an array are numbered starting with 0. The number is called the index or subscript. When you use an array you need to use a subscript to specify which item, or element, in the list is to be used.
In this example, the tortoise says sayings[0], of "Ready".
An array can also use variables as the subscript:
In this example, num is 1, so when the tortoise says sayings[num] he says "Set".
In this module, you will declare and use arrays. An array is a variable that is a list.
You will create arrays of words, numbers, or objects, then use loops to process the entire array.
Goal:
- Learn to declare and use arrays (lists)
- Understand how arrays can act on groups of objects together
- Learn to create array of different types, including objects.
- Use the control structures that operate on arrays
- Define parallel arrays and name ways to use them
- Be able to use arrays of segments
In order to do this you will:
Objectives:
- Declare a variable to be an array.
- Create code to assign initial values to an array.
- Use subscripts or index to access the elements of the array.
- Utilize loop control structures to process all of the elements of the array.
- Create and process arrays of different data types, including arrays of objects.
- Understand the purpose of parallel arrays and ways to use them.
- Experiment with arrays of segments, such as the segments of an elephant's trunk or tail.
Please study the material at each of the links below.
An array of animals: An array of SJointedModel contains, yeti, tortoise and stuffedTiger
/alice/videos/alice-array-objects.mp4
The animals talk: Parallel Arrays: One array contains animals, the other the things they say
/alice/videos/alice-animals-talk.mp4
Who's the tallest?: People are in an array, a loop is used to find the tallest.
/alice/videos/alice-tallest.mp4
Animals counting: An array of animals take turns to count
/alice/videos/alice-array-counting.mp4
Birds spread wings and say something: An array of birds perform
/alice/videos/alice-bird-array.mp4
Fish swim to cave with procedure: Each fish swims to cave with procedure
/alice/videos/alice-fish.mp4
- Segments of an elephant's trunk as an array: The segments of an elephant's trunk, tail and a few other things are an array.
Self Study Questions: What have you learned?
Discussion questions: What do you think?
Active Learning
Create a project using arrays
Glossary for arrays lesson
Full Glossary