Outline for October 6, 2021

Reading: §6.1–6.8}
Due: Homework 1, due October 6, 2021

  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]

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Matt Bishop
Office: 2209 Watershed Sciences
Phone: +1 (530) 752-8060
Email: mabishop@ucdavis.edu
ECS 235A, Computer and Information Security
Version of October 4, 2021 at 11:36PM

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