2.1 - Elements of computational thinking

• Discuss the need for and purpose of abstraction

  • Removal of unnecessary elements
  • Uses symbols to represent elements of a problem
  • Increase chance of creating the program successfully
  • Reduces programming time and factors that can detract from the program
• Mary created the program as a series of sub-programs that can be reused.

  Describe one benefit of Mary creating reusable program components

  • the components can be used in a future program they do not need to be rewritten
  • they have already been tested it will save time
• Explain and evaluate the use of re-useable components

  • One piece of code can be used in multiple places / called many times
  • Use of subroutines / procedures / functions
  • Use of classes
  • Use of external libraries
  • The use of a class allows replication
  • Faster development
  • Faster/easier future adaptation
  • Better performance of program
• Discuss the need for concurrent processing and the benefits and drawbacks of using this

  • Processes are happening at the same time/at overlapping times
  • One process may need to start before a second has finished
  • Individual processes are threads, each thread has a life line
  • One request will be sent to the server, this will have a thread

  Benefit

  • Multiple requests to the server can be made at the same time

  Drawback

  • Programming will need to restrict access to the database of seats/sales
  • Record locking will need implementing – more complex programming
• Describe what is meant by the term ‘concurrent processing’.

  • Multiple processes being executed at the same time appearing to happen simultaneously
  • Giving processes a slice of the processor time
  • Having multiple processors each carrying out a different process
• Explain why concurrent processing is needed to allow multiple users to log in and interact with game elements at the same time

  • Game could have large number of requests to the server at a time, server needs to respond in reasonable time
  • having multiple processors handling the different requests would increase response time
  • use record locking to stop edits if someone else has access to data
  • Different users will have different response times therefore the processor can still handle other requests so that the performance for other users is not affected
• A programmer is developing an aeroplane simulator. The user will sit in a cockpit and the simulated environment will be displayed on screens around them. Describe how caching can be used in the aeroplane simulator.

  • Store data that has been used in cache/RAM in case needed again
  • e.g. store design of the weather/a cloud/external environment