Lecture 1

Question 1

what does the break keyword do?

Answer 1

Exits the loop

Question 2

how do you make an infinite loop?

Answer 2

while True:

Question 3

what is a list? (3)

Answer 3

1 sequence data type
2 enclosed in [], data separated by commas
3 can contain data of many different types.

Question 4

how do you access a list item within a list? (syntax)

Answer 4

listname[index of inner list[index of inner list item]]

Question 5

what is the syntax for using the range object to create a list with numbers 1-10?

Answer 5

a=list(range(1, 11))

Question 6

how do you create a list using list comprehensioN? (ex: squares of first 3 numbers)

Answer 6

squared_numbers = [x**2 for x in range(1, 4)]

Question 7

what does append method do and what is syntax?

Answer 7

listname.append(x)
adds a single element x to the end of a list

Question 8

what does the extend method do and what is the syntax?

Answer 8

listname.extend(x)

merges another list x to the end of the list

Question 9

what is the insert method and what is the syntax?

Answer 9

listname.insert(index, x)

inserts element x at position index

Question 10

what is the remove list method and what is the syntax?

Answer 10

listname.remove(value)

removes the first occurrence of element x from listname.

Question 11

what is the pop method and what is the syntax?

Answer 11

listname.pop(index)
removes the LAST element of a list. if an argument is passed, that index item is removed.

Question 12

what is the index method and what is the syntax?

Answer 12

listname.index(x)

searches for a given element from the start of the list and returns the position of the first occurrence. Throws error if not found.

Question 13

what is the count method/syntax?

Answer 13

listname.count(x)

Counts the number of occurrences of an element x in a list listname.

Question 14

sort method + syntax? (+3 things to remember)

Answer 14

listname.sort(reverse=True/False, key=function to specify sorting criteria by returning it)

**you have to use the keywords by name in the argument eg key=a

**you don’t need the () when naming the function in this syntax

*** does not work when sublists are involved

Question 15

reverse method + syntax?

Answer 15

listname.reverse()

reverses the list

Question 16

swapcase method + syntax

Answer 16

returns a string with all the cases changed.

stringname.swapcase()

Question 17

what is a way to reverse a list without the reverse method?

Answer 17

listname[::-1]

Question 18

len method + syntax

Answer 18

returns number of elements present in a list

syntax:

x=len(listname)

Question 19

max/min method + syntax

Answer 19

return max/min value in a series
min(listname)
max(listname)

Question 20

what is the definition of scope, and wht is the scope of a variable created iwthin function a?

Answer 20

scope=where our variables can be accessed!
the scope is only within function a.

Question 21

what is a global vs local variable?

Answer 21

local = defined within the function
global = defined outside all the fuctions in the general code

Question 22

how do you use a global variable wtihin a function?

Answer 22

global variablename allows you to pull a variable from outside the function and make it usable within the function

Question 23

how would you replace values in a list?

Answer 23

a=[list]
i=a.index[value to replace]
a[i]=new value

Question 24

how would you swap values in a list?

Answer 24

a = 2
b = 4
a,b = b,a
print(a,b)

Question 25

what is a nonlocal variable and what are its limitations?

Answer 25

The nonlocal keyword is used in nested functions to reference a variable in the parent function.

won’t work on local or global variables and therefore must be used to reference variables in another scope except the global and local one.