Notes

Outline

Announcements Monday labs cannot be held due to a scheduling conflict -- go to Tuesday’s There are four Tuesday labs: 8:30, 9:30, 1:30, 2:30 The term’s calendar is posted including Midterm dates; it’s subject to change RGB Yellow = Full, Full, Zero intensity

What the Digerati Know Other people can teach you computer applications or you can figure them out for yourself

Learning New Tools How do we learn to use new tools? Be taught to use them -- car, bicycle Reading the owner’s manual -- chain saw Figure them out ourselves -- CD player

Learning New Tools How do we learn to use new tools? Be taught to use them -- car, bicycle Reading the owner’s manual -- chain saw Figure them out ourselves -- CD player Software designers wanting you to learn their tool ASAP, try for ‘intuitive’ Consistent Interfaces -- build on experience Suggestive icons -- bypass terminology Metaphors -- exploit analogous reasoning

A New Application Find: consistent   interface icons metaphor

Standard Functionality Most applications have File and Edit

What does ‘New’ Mean? ‘New’ means create a ‘blank instance’ To understand ‘blank instance’ know that information has properties as well as content which are all stored in a structure with a place for everything A ‘blank instance’ is simply the structure without any of the content

“Click Around” Software designers use standard ideas to make applications intuitive To learn a new application, check it out by clicking around Take a minute to ... Look under all menus to see operations Follow the  “…” for menu operations Try to recognize what the icons mean

“Blazing Away” Learn an application fast by trying it Beginning with a new instance, assertively try menu items Expect to fail and make a mess Exit the application, and if you are asked “Save?” reply “No” Try repeatedly until becoming familiar

To Learn A New Tool Software systems build on a consistent interface, standard metaphors, etc. Expect to teach yourself applications Do so by familiarizing yourself with the features … “Clicking Around” Assertively try out the features, “Blaze Away,” watching what they do Be efficient -- stay focused, don’t type a lot when you expect to exit

Mac or PC??? Arguments about which is better, Mac or PC, create only heat, no light They are more alike than different Any Fluent person can use both

Differences & Similarities Different vendors will produce similar software for the same task Superficially, the GUIs use similar features Fundamentally, the task largely determines how the software must work … they must be similar

Differences & Similarities Different vendors will produce similar software for the same task Superficially, the GUIs use similar features Fundamentally, the task largely determines how the software must work … they must be similar Implications … Know one word processor, learn others fast SW differences: mostly glitz, convenience Don’t accept lousy … switch to other SW

Another Implication If SW is similar at core, computations can be taught independently of vendor

Another Implication If SW is similar at core, computations can be taught independently of vendor … consider text searching and replacement

Replacement Two strings are required: search string and substitution string Adopt a notation:  search û substitute

Notation Example Illustrating the use of the notation Using the replacement The sentence Becomes It’s easy to express substitutions

Placeholder Technique The Problem: Eliminate single instances of a string without removing doubles

Placeholder Technique The Problem: Eliminate single instances of a string without removing doubles

Placeholder Technique The Problem: Eliminate single instances of a string without removing doubles

Thinking of the Input Roses are ¿red¿¿Violets are ¿blue¿¿... Deleting the single ¿  deletes them all!

Thinking of the Input Roses are ¿red¿¿Violets are ¿blue¿¿... Deleting the single ¿  deletes them all! Placeholder technique … Substitute a placeholder for the longer string ¿¿ û  # Yielding Roses are ¿red#Violets are ¿blue#… Next, delete the shorter string   ¿ û e Yielding Roses are red#Violets are blue#…

Placeholder Replaced Finally, replace the placeholder with the original long string # û ¿¿ Yielding Roses are red¿¿Violets are blue¿¿… The intended result Summarizing the placeholder longstring û placeholder shortstring û e placeholder û longstring

Summarizing Humans must learn to use tools Software designers want you to learn easily SW uses consistent interface, metaphors, … Teach yourself applications by “Clicking Around,” and “Blaze Away” SW for a task must share core features Learn app.s independently of vendor