loops

Question 1

what is a loop in python

Answer 1

In programming, this process of using an initialization, repetitions, and an ending condition is called a loop. In a loop, we perform a process of iteration (repeating tasks).

Question 2

what is Definite iteration

Answer 2

Where the number of times the loop will be executed is defined in advance (usually based on the collection size).

Question 3

What is Indefinite iteration

Answer 3

where the number of times the loop is executed depends on how many times a condition is met.

Question 4

what is a for loop

Answer 4

a type of definite iteration. (When a program needs to iterate a set number of times)

In a for loop, we will know in advance how many times the loop will need to iterate because we will be working on a collection with a predefined length

Question 5

what is a tempory variable

Answer 5

that is used to represent the value of the element in the collection the loop is currently on.

Question 6

how to layout a for loop

Answer 6

for <temporary> in <collection>:</collection></temporary>

<action>

ingredients = ["milk", "sugar", "vanilla extract", "dough", "chocolate"]

for ingredient in ingredients:
print(ingredient)

In this example:

ingredient is the <temporary>.

ingredients is our <collection>.

print(ingredient) was the <action> performed on every iteration using the temporary variable of ingredient.
</action></collection></temporary></action>

Question 7

what is the ( in ) used for in a ( for ) loop

Answer 7

An in keyword separates the temporary variable from the collection used for iteration.

Question 8

what is <collection> in a for loop</collection>

Answer 8

A <collection> to loop over. In our examples, we will be using a list</collection>

Question 9

does a tempory variable need to be defined before hand ?

Answer 9

A temporary variable’s name is arbitrary and does not need to be defined beforehand.

Question 10

do we need to indent a for loop ?

Answer 10

If we ever forget to indent, we’ll get an IndentationError or unexpected behavior.

Question 11

example for loop

Answer 11

sport_games = [“football”, “hockey”, “baseball”, “cricket”]

For sports in sport_games:
print(sports)

Question 12

how to use the range directly in our for loops as the collection to perform iteration ?

Answer 12

for temp in range(6):
print(“Learning Loops!”)

Would output:

Learning Loops!
Learning Loops!
Learning Loops!
Learning Loops!
Learning Loops!
Learning Loops!

Question 13

what is the structure of a while loop

Answer 13

The structure follows this pattern:

while <conditional>:</conditional>

<action>

Let’s examine this example, where we print the integers 0 through 3:

count = 0
while count <= 3:
# Loop Body
print(count)
count += 1

output: 0, 1, 2, 3
</action>

Question 13

what does a ( while ) loop do

Answer 13

a while loop and is a form of indefinite iteration ( where the number of times the loop is executed depends on how many times a condition is met. )

A while loop performs a set of instructions as long as a given condition is true.

Question 14

what does the str ( ) do

Answer 14

converts the variable from an integer to a string

Question 15

what is the purpose of the len ( ) in a loop list

Answer 15

If we use the length of the list as the basis for how long our while loop needs to run, we can iterate the exact length of the list.

We can use the built-in Python len() function to accomplish this:

Length would be equal to 5
length = len(ingredients)

Question 15

can you use while loops to iterate through a list

Answer 15

yes

Question 16

how do you construct 2 variables to make a for loop

Answer 16

length = len(ingredients)
index = 0

while index < length:
print(ingredients[index])
index += 1

Question 17

what does the ( break ) do in a loop

Answer 17

Once item is found in a list the break command will stop the search

if item == “knit dress”:
break

Question 18

what does the continue loop control do

Answer 18

if we want to print out all of the numbers in a list, but only if they are positive integers. We can use another common loop control statement called continue.

Question 18

what is a nested loop

Answer 18

if we wanted to print each item in the list we would actually need to nest our loops to be able to loop through each sub-list.

Loop through each sublist

for team in project_teams:

# Loop elements in each sublist

for student in team:
print(student)

This would output:

Ava
Samantha
James
Lucille
Zed
Edgar
Gabriel

Question 19

how do we nest loops in pyhton example code

Answer 19

for groupes in group:
for name in group:
print(name)