week 9 functions with lists

Question 1

defining lists

Answer 1

can be hardcoded, list function, or from a file

Question 2

mutable types in functions

Answer 2

list, dictionary, and set that are passed into function are also altered in the workspace

Question 3

index method

Answer 3

allows you to search ordered object for certain value and returns the index

Question 4

expense

Answer 4

the number of comparisons needed to find something (in reference to methods)

Question 5

ordering/sorting data

Answer 5

increases efficiency because you know where stuff is and can select certain chunks to search for something

Question 6

binary search

Answer 6

reducing search items by sorting data

Question 7

scope

Answer 7

part of a program that variable/function exists

Question 8

local variables

Answer 8

variables defined in functions, the scope is within the function

Question 9

global variable

Answer 9

created outside function, scope is from defining statement until the end of the file

Question 10

global statement

Answer 10

used to change a global value and create a global value inside a function (use keyword global, then state function name)

Question 11

do modifications to mutable types within a function need a global statement?

Answer 11

no

Question 12

function scope

Answer 12

from function definition until the end of the file

Question 13

namespace

Answer 13

maps names to objects

Question 14

locals()

Answer 14

prints all local variables

Question 15

globals()

Answer 15

prints all global variables

Question 16

3 nested scopes

Answer 16

built-in scope, local scope, global scope

Question 17

built-in scope

Answer 17

contains built-in python names, like int, str, list, etc

Question 18

scope resolution

Answer 18

process of searching for object name in available namespaces

Question 19

order of scope resolution

Answer 19

local, global, built-in

Question 20

pass-by-assignment

Answer 20

when the function is called, new local variables are created in the function’s local namespace, parameter names are binded to the passed arguments

Question 21

immutable objects

Answer 21

modifications are limited to function

Question 22

mutable object

Answer 22

modifications affect the full scope

Question 23

how do you avoid changes to mutable objects in functions?

Answer 23

create a copy of the object
ex:
copy = item_list[:]

Question 24

list

Answer 24

mutable container with sequential order, elements can be accessed through indexing

Question 25

in-place modifications

Answer 25

elements can be added or removed at any time

Question 26

list methods

Answer 26

operations to add or remove elements to a list, lists can also be sorted or reversed

Question 27

insert method example

Answer 27

list.insert(1, ‘string’) –> adds new element, ‘string’, at index one

Question 28

for loop

Answer 28

can iterate over each element of a list

Question 29

index error

Answer 29

trying to access an index out of range

Question 30

enumerate()

Answer 30

function that iterates over a list and provides an iteration counter

Question 31

all(list)

Answer 31

true if there are no 0s in list

Question 32

any(list)

Answer 32

true if any element of list is true

Question 33

max(list)

Answer 33

returns max, same structure for min and sum

Question 34

list nesting

Answer 34

list of lists

Question 35

how do you index nested lists

Answer 35

my_list[0][0] –> returns 1st element of 1st list in my_list

Question 36

multidimensional data structure

Answer 36

data structure that contains more layers of data

Question 37

nested for loops

Answer 37

can be used to access elements of nested lists

Question 38

slice notation

Answer 38

read multiple items from list and create new one with desired elements

Question 39

stride

Answer 39

step size for indexing and accessing elements
my_list[start:end:stride]

Question 40

sorted()

Answer 40

sorts list and makes copy instead of modifying existing

Question 41

list method key

Answer 41

argument that specifies a function to be applied to each element before comparing

Question 42

how do you use sorted function with lowercase key?

Answer 42

sorted(names, key=str.lower)

Question 43

how do you use sorted function with reverse key?

Answer 43

sorted(names, reverse=True)