Python iterate & enumerate() Explained

Digital Marketing

🧠 Want to loop through lists and get both the value and its position? In this beginner-friendly Python tutorial, we’ll explore how to iterate over lists using regular for loops and how to supercharge your loops with the built-in enumerate() function. Understanding these  Concepts are essential for writing clean, efficient, and professional-grade Python code. https://1stepgrow.com/advanced-data-science-and-ai-course/  Perfect for students, beginners, or anyone looking to master Python list handling with more control and clarity.

Transcript

00:00okay how can we get the index you can use the brute force method so you can say for i in range

00:13starts from zero goes up to length of shopping underscore list now what does this tell us it

00:19tells us that the range starts from index zero goes up to number of shopping list minus one

00:25because the last element is exclusive the first element is included the last element is not

00:31included and if i would print the value of i i would get these values zero one two three four

00:37five six seven eight till the value 11 okay that means i have 12 elements in the list the list

00:44starts at index zero goes up to index 11 now i can say shopping okay i will just show you a couple

00:52of examples i can say shopping underscore list index zero is equal to curd am i right similarly

01:02shopping list index one is equal to

01:07beat so on and so forth right so similarly when i get the index i can use the index to get the value

01:15so i can say shopping underscore list index i so i would get the value zero curd one wheat two

01:24chocolate three rice four milk so on and so forth this is one way of doing it but there is a more

01:30elegant way and that elegant way is using a built-in method called enumerate now when you write the word

01:37enumerate you will see that enumerate becomes green in color that means enumerate is like the type method

01:43or the print method or the len method it's a built-in python method now what does enumerate do

01:49it takes the iterable in this case it takes the shopping list and it gives you an enumerate object

01:56now the enumerate object is something that cannot be seen by our eyes just like the range object cannot

02:01be seen by us right the range object cannot be seen by us but how can we see the range object we can

02:09see the range object when we convert the range object to a list that time we are able to see the

02:14range object we are able to see what all the range object holds and or when we iterate over the range

02:21object then we are able to see the range object am i right print time we are able to see over the range

02:30object similarly in the enumerate we are not able to see the values of the enumerate right how can we

02:37the values of the enumerate by converting it to a list so i can say list of enumerate e-m-u-m-e-r-a-t-e

02:44underscore list so what are we doing we are converting okay oh sorry my bad my bad

02:54i just got distracted for a second okay so now enumerate underscore list is not defined okay

03:01list so what have i done i have converted the enumerate to this and i get a list where every

03:08element not only contains the value but it also contains the index if you just look at the value

03:13and forget about the circular encapsulation if you just look at the value you will see that

03:18you not only get the index but you also get the value of the element it tells us that at index 0

03:25i have the element curd at index 1 i have the value wheat in index 2 i have the value chocolate

03:31in index 3 i have the value rice so on and so forth this is the power of this is the utility

03:37of an enumerate function now enumerate is also an iterable the enumerate thing is also an iterable

03:43so i can iterate over the enumerate so i can say for element in enumerate e-n-u-m-e-r-a-t-e

03:53enumerating what enumerate the shopping underscore list

03:56okay print element what would you get you would get in circular bracket the index and the value now

04:04again please don't try to wrap your head around the circular bracket we have not covered that yet

04:10right but you just look at the values you get the index and you get the element now what is this

04:17circular bracket thing so if i say type of element you will see that element is of type tuple

04:27so just like a list is encapsulated in circular brackets and i have a number of elements inside

04:33the list right a list is encapsulated in circular brackets and i have some elements encapsulated in

04:39the list similarly a tuple is encapsulated in circular brackets and i can have some elements

04:47inside a tuple this is a tuple now what is the main difference between a list and a tuple

04:53so for example if i have a list of numbers like this this is a type list that is for sure we have

05:03like done list in details right now now what do we know about list a list is mutable that means you can

05:08change the elements of the list that means if i create a variable called new underscore numbers

05:15and i assign it to numbers and then i say new underscore numbers index zero is equal to thousand

05:26now if i print the value of new underscore numbers and i print the value of numbers you would see that the

05:36value of index zero has changed from two ninety two to two thousand that means i was able to modify

05:44an element at index zero hence lists are mutable list can be modified

Category

Transcript

Be the first to comment

Recommended