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TEST 1 MATERIAL
Sequences
common operations/functions:
+, *, len
indexing via [i]
slicing via [s:e] and [s:e:n]
traversal
can traverse using 'for X in SEQ: ... X ...'
can traverse using 'for i in range(len(SEQ)): ... SEQ[i] ...'
can test membership using 'X in SEQ' and 'X not in SEQ'
each type of sequence has its own type-specific methods
unlike functions, called as SEQ.METHOD(INPUTS)
strings
sequence of characters, immutable
methods
type related: isalpha, isupper, islower, isspace
case related: capitalize, upper, lower
format related: center, rjust, strip, rstrip
search related: count, find, replace
traversing a string
by character vs. by index
building a copy of a string, char-by-char
examples: palindrome, rotation, cipher
lists
sequence of arbitrary items, mutable
methods
search related: count, index
order related: sorted, reversed, sort, reverse
updates: append, extend, insert, remove
strings to lists
string split method
splitting user input into words/numbers
building lists
building a list, item by item
list comprehensions, conditional comprehensions
examples: dice stats, averaging, acronym
big data
e.g., text files --> file stats, literary fingerprints
e.g., Trump tweets --> average length, word/char frequencies
e.g., dictionary --> word stats, find anagrams
e.g., Trump metadata --> percent retweets, most favorited, day stats
User Interaction
input/output
input: numbers must be converted (int, float)
print: automatically separates values with spaces, adds newline
can avoid spacing using concatenation, e.g., str(percent)+"%"
can avoid new line using end=""
files
open a file using open function
with open(filename, "r") as infile:
with open(filename, "w") as outfile:
file input methods:
read() vs. read(1) vs. readline()
can use string split method to structure complex data
file output methods
write(), use "\n" for a line break
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