Outline for January 31, 2018

Reading: §6

  1. Sequences
    1. Sequences are a series of values in a particular order
    2. In Python predominantly strings and lists but also sets and tuples
  2. Strings
    1. Sequence of characters (characters are strings of length 1)
    2. Strings are immutable; really important for functions
  3. Basic string operations
    1. +, concatenation for strings
    2. *, repetition repeats given value
    3. len() returns length of sequence
    4. s in str returns True if s is a substring of str, False otherwise
  4. Indexing, var[position]
    1. Count from 0 to len(var)−1
    2. Position can be a negative number to count from right
  5. Assignment with indexing doesn’t work as strings immutable
    x = "hEllo"; x[1] = "e" produces an error
  6. Slicing, var[start:end]
    1. Value at index end not included in slice
    2. If omitted, starting value defaults to 0 and ending value defaults to last index + 1
    3. Can use negative index
  7. Looping over strings: for i in str
  8. Example program [strstuff.py]

Matt Bishop
Department of Computer Science
University of California at Davis
Davis, CA 95616-8562 USA
Last modified: Version of January 30, 2018 at 11:26PM
Winter Quarter 2018
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