Weeks7 & 8


From last week:

Assignment #5, discussion of fancier approach

Build a web page in which the user can type or paste a paragraph or more of text. When done, the user can press a button which "analyzes" the text. The analysis consists of two tabulations: the frequency of occurrence of every letter and punctuation mark (lowercase and uppercase letters are considered the same so that "a" and "A" are identified) and the frequency of occurrence of every character pair (or digraph -- in which "ab" is not the same as "ba") is tabulated and presented on the page.

Finally, when a second button is pressed, new random text is generated and placed somewhere else on the page. The newly generated text should be generated with the probabilities of letters' occurrences matching the frequency of occurrence within the user's text. That is, if the occurrence of "e" accounts for 12% of the characters used, then the probability of generating an "e" should be 0.12.

For extra credit, make it so that the probabilities associated with digraphs match their observed frequencies. (Another button should be deployed on the page for this feature.)

Approach using two arrays

Approach using associative arrays

Even fancier approach

More on associative arrays

Uneven probabilities


The thing I worked on in class on Tuesday.

How to find the largest element(s) in an associative array (conventionally, and using objects)

A better version of the above

New material:

Basic Form components

Document Object Model

Probing DOM

Windows, locations and frames


review: document.write and innerHTML and appendChild( )


Assignment #6 - due to be announced

Make a page containing two inputs (m and n) and three buttons. Whenever any button is pressed, construct an m by n multiplication table (illustration below). One button should use document.write, another: innerHTML, and the third should use the DOM methods (createElement, appendChild, etc.)

 


Images are from Museum of Wonders or Curiosities of the World, Henry Davenport Northrop, D.D. copyright 1892.