LEARN TO PROGRAM WITH ALICE

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LEARN TO PROGRAM WITH ALICE

• Xiannong Meng
• Computer Science Department
• Bucknell University

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Lecture Nine

• Summary

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Computer Science ConceptsGeneral Concepts

• Program a set of instructions that tell the
  computer what to do
• Programming language instructions following a
  fixed set of syntax
• Different levels of programming language
• High level language
• Machine level language
• Assembly language

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Computer Science ConceptsGeneral Concepts --
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• Object an entity that has data and methods (or
  states and actions)
• Algorithm a list of actions to perform a task or
  solve a problem
• Pseudo-code when an algorithm description is
  detailed and very close to the actual program
  code, this description can be called pseudo-code

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Computer Science ConceptsGeneral Concepts --
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• Four stages of programming (This is in Alices
  term, in software engineering, more steps are
  involved)
• Read understand what needs to be done
• Design create scenes and actions associated with
  each scene, using storyboard
• Implement turn the design into code
• Test make sure program works properly in various
  conditions

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Computer Science ConceptsGeneral Concepts --
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• Abstraction hide details to a lower level so the
  code modules are coherent
• Method a collection of code to accomplish a
  specific task which would change the state of a
  program
• Function a collection of code to compute a value
  which would not change the state of a program

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Computer Science ConceptsGeneral Concepts --
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• Parameters an object that is used to pass
  information from one object to another or from
  one method to another
• Selections if-then-else
• Repetition loop, while, for
• Counting loop loop, for
• Conditional loop while

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Computer Science ConceptsGeneral Concepts --
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• Inheritance creating an object using an existing
  object as the base

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Computer Science ConceptsAlice Specific Concepts

• Virtual world an animation is implemented in
  Alice as a virtual world
• Alice object basic entity in Alice that has
  features
• Dimensions height, weight, depth
• Directions up, down, forward, backward, left,
  right
• Center

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Computer Science ConceptsAlice Specific Concepts
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• Distance measured from the center of the objects
• Location in a 3-D space, described by (x,y,z)
• Alice IDE (integrated develop environment)
• Object tree
• Detailed pane
• World view
• Event editor
• Method editor

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Computer Science ConceptsAlice Specific Concepts
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• Vehicle an object can be a carrier of another.
  The carrier is called a vehicle
• Event an event is something that happens (a
  change of the state)
• Event-handler method that responds to an event