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== DOM == | == DOM == | ||
c=document.getElementById("c") | |||
== A Script == | == A Script == |
Revision as of 10:34, 24 September 2012
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A Computer Glossary
Charles & Ray Eames 1968
Produced for the IBM Corporation pavilion at Hemisfair, the 1968 Worlds Fair in San Antonio, Texas.
Code
http://rosettacode.org/wiki/Category:Draft_Programming_Tasks
http://rosettacode.org/wiki/99_Bottles_of_Beer
Expression / Evaluation
Some expressions for the console...
5
3
"Tristram"
'SHAndy'
Operations
5 * 3
100 - 1
3 * 8
"Tristram" + "Shandy"
Operations: Functions
Math.sqrt (25)
Math.sqrt (26)
Objects
"Tristram".toUpperCase
?!
"Tristram".toUpperCase()
Assignment
Assignment is the process of storing an expression in a "name", called a variable.
x = 5 * 3
name = "Tristram"
Assignment ++
x = x + 1
x += 1
x++
name = name + " Shandy"
DOM
c=document.getElementById("c")
A Script
BASIC
10 INPUT "What is your name: ", U$
20 PRINT "Hello "; U$
30 INPUT "How many stars do you want: ", N
40 S$ = ""
50 FOR I = 1 TO N
60 S$ = S$ + "*"
70 NEXT I
80 PRINT S$
90 INPUT "Do you want more stars? ", A$
100 IF LEN(A$) = 0 THEN GOTO 90
110 A$ = LEFT$(A$, 1)
120 IF A$ = "Y" OR A$ = "y" THEN GOTO 30
130 PRINT "Goodbye "; U$
140 END
from wikipedia:BASIC
Branch
http://en.wikipedia.org/wiki/Conditional_jump
IF-THEN-(ELSE)
Making functions
Function / Callback
Exercise: Canvas
Handouts
Assignment, GeneralImperative + ProgramHighLow
Debug / Trace
Scope
Loop
Afternoon: Image Manipulation
The CanvasPixelArray contains height x width x 4 bytes of data, with index values ranging from 0 to (height x width x 4)-1.
context.getImageData
context.putImageData
! Come up with examples showing variable scope.