Outline for February 13, 2012

Reading: §14

1. Objects, references, aliasing (Correction from last lecture)
   1. Assign “banana” to variables a, b
   2. For strings, one copy (a is b is True) [immutable]
   3. For strings, a = "hello"; b = a; then a is b is True
   4. Also, a = "hello"; b = a[:]; then a is b is True
   5. For lists, multiple copies (a is b is False [mutable]
   6. For lists, a = [ 1, 2, 3 ]; b = a; then a is b is True
   7. But . . . a = [ 1, 2, 3 ]; b = a[:]; then a is b is False
2. Lists as parameters: can change list elements in function and they are changed in caller [args2.py]
3. List methods
   1. Add elements to, remove elements: L.append(x), L.extend(ls), L.insert(i, x), L.pop(), L.remove(x)
   2. Element ordering: L.reverse(), L.sort()
   3. Other: L.count(x), L.index(x)
   4. Example use: linear search [linsearch.py]
4. Tuples
   1. Used to group data
   2. Like lists, but immutable

ECS 10, Basic Concepts of Computing Winter Quarter 2012