Python (Tim)

Front 1

Examples of unordered collections

Back 1

Dictionaries = {key : value}

Sets = {list}

Front 2

d = {"apple" : "red", "Lemon":"yellow", "lime":"green"}

d["banana"] = "yellow"

Back 2

A dictionary is bein initialized with fruit as keys and their colors as the values. Then we proceed to create a new element into the dictionary.

Front 3

del d["banana"]

Back 3

it deletes the element banana from the d dictionary.

Front 4

d.clear()

Back 4

it erases every element from the d dictionary.

Front 5

d.get("something") ???

Back 5

it returns whatever the key was given.

Front 6

why is it not a good idea to add or delete elements while iterating through a dictionary?

Back 6

It is not a good idea because each time an item is added or deleted the order of the dictionary changes.

Front 7

d = {"apple" : "red", "Lemon":"yellow", "lime":"green"}

order_keys = list(d.keys())

order_keys.sort()

for f in order_keys:

print(f + " is " + d[f])

Back 7

This is a way of making sure that we iterate through the dictionary in a sorted manner, every single time.

Front 8

d_tuple = tuple(d.items())

Back 8

it creates a tuple that has tuples as their values. Each tuple has the key and the values of the each dictionary element.

Front 9

for a in d_tuple:

fruit, color = a

print(fruit + " is " + color)

Back 9

it is unpacking a tuple and assigning their values to variables fruit and color.

Front 10

what does the .join() function do?

Back 10

It lets us add text to every block of text in a variable.

Better explanation needed.

Front 11

what does the .copy() function do when use on a dictionary?

Back 11

It creates a copy of the dictionary that is being inputed without modifying the data of the dictionary.

Front 12

what does the .update() function do when use on a dictionary?

Back 12

it adds two dictionaries together. Thus modifying the dictionary that is being updated.

Front 13

How is a set initialize?

Back 13

It can be initialize in two ways.

s = set(1,2,3,4,5) //This way a set can be intialize with zero items.

s = {1, 2, 3, 4}

Front 14

What does the union() function do on functions.

Back 14

It returns the union of two sets.

EXAMPLE:

un = s.union(other_set)

Front 15

What does the & and intersection function do?

Back 15

They return the values that are present in both sets.

EXAMPLE:

un

Front 16

what does the difference function do to a set.

Back 16

It returns the values of the set minus the set that is being inputed to the difference function.

example

even.difference(squares)

returns the values of even minus the values of squares.

Front 17

what does the symmetric_difference() function do on a set?

Back 17

It returns the result of both dictionaries join together without the values that appear on both dictionaries. It does the opposite of & and joins the dictionaries together.

Front 18

what is a frozen set?

Back 18

It is a set that is immutable.