Creating Web documents

1
Creating Web documents

• JavaScript modeling dog behavior
• general modeling concepts
• JavaScript review

2
Dog behavior

• Feed dog
• Dog gains /loses weight
• Pet dog
• wag tail
• show anger

3
JavaScript parts

• variables time last fed, timing interval, weight
• functions
• seconds_elapsed calculates time since last
  feeding
• startgame, stopgame,
• feeddog,
• petdog,
• change function invoked each interval
• form used to display weight and condition
• image tag used to display appropriate image of
  dog (possibly animated gif)

4

• Pet

8
Concepts

• Model a representation of something
• Models can be realisticbased on our
  understanding of how things work (all science is
  building testing models) OR fanciful OR
  in-between
• Models can be deterministic and/or
  non-deterministic (based on probabilities, aka
  'stochastic' processes)
• Dog model had both.
• Models can have discrete and/or continuous
  features.
• Dog model basically continuous weight. Tail
  wagging was based on threshold value.

9
Data driven applications

• Applications are said to be data-driven if they
  are based on data, generally externally
  supplied data.
• John Klima had data driven applications, for
  example, the currency project that controlled the
  birds.
• Visualization is the name for the technique of
  displaying (real) data in ways that could lead to
  insights, including scientific discoveries.

10
JavaScript overview

• You have seen
• use of Date
• status bar
• image slide show
• dice throw
• image swap based on mouse over
• form verification
• dog model
• (will see calculation of bills)
• GENERALIZE! Use features to put together your
  ideas.

11
JavaScript features

• variables
• local global (outside of any function)
• arrays
• built-in functions Date, Math.random,
  document.write, others.
• functions
• forms (for input output)
• named image tags
• events onMouseOver, onSubmit, onMouseout
• setInterval (setting up handler for timed event)
• If, For, return statements

12
Homework

• Catch up on postings (including posting idea for
  project 3, including keywords and description).
  Read postings!
• Use google.com to look up how to do things in
  JavaScript.