Know what is the difference between filter, reduce and map: map: Takes a function f, and a list L1, and returns a list L2 obtained by applying f to every element of L1. Say f is a function that takes x and returns 2x. Then, map(f, [1,2,3,4]) returns [2,4,6,8]. reduce: Takes a binary operator f, a list L and a seed value (or identity element). It returns the seed value if the list is empty. Otherwise, it applies the binary operator f to the seed and first element of L, then applies f to the result of this and the 2nd element of L, and so on till L is exhausted. The result is returned. This can be seen as a generalization of factorial function. filter: Takes a boolean function f and a list L1. It applies the function to each element of L1, and list of those elements that give true is returned. #insmot
In case anyone need more information about the difference between filter, map and reduce: Difference 1: 1. 'Map' takes all objects in a list and allows you to apply a function to it. The result is usually the same quantity of items as in the main list but with some execution(as specified in the function). 2. 'Filter' takes all objects in a list and runs that through a function to create a new list with all objects that return True in that function. Not necessary that it will output same number of items as present in the main list. Difference 2: 1. In Map you can use multiple iterables definition : map(function_object, iterable1, iterable2,...) 2. Whereas in filter only one iterable can be used definition : filter(function_object, iterable) Difference 3: Further in filter the function_object has to return boolean only. Hope it helps! :) #insmot
oh god! you are simply answering all the questions that pop my head. thank you navin. you have no idea what a great part you are holding in my life. because of you, im fearless and ready to learn programming. thank you for saving my life.
finally found a good tutor who does'nt just dump all the codes and and leave logic behind completely making it boring and useless to watch. really amazing sir.
Navin sir can u make more videos and more concepts as soon as possible because we are understand very easy with ur explaination NOTE : TRY TO MAKE SOME PROJECTS AND SOFTWARE USING THIS CONCEPTS
This is so amazing! I learnt a whole lot about not just lambda from this video, but also these three other useful (albeit advances) functions! Thank you so much!
You are a teacher of note ... not only a coder ... Thanks for the effort. If I can do anything to help you expand ( other than liking or subscribing ), let me know.
Hello Sir, Thanks so much for the lessons. I have coded factorial of a number using reduce functions. Its working:-) from functools import reduce s=[] n=int(input("Enter the number")) for i in range(n+1): if i==0: continue else: s.append(i) print(s) total = reduce(lambda a,b: a*b,s) print(total)
@@MegaCherry0 This is a reply after 7 months but I can confidently say that this is the best channel for python. I regret not discovering this channel earlier
Than you sir, after working out this problem myself in laptop, this become simple now... You are a greater teacher and thanks for making me to sit here till above 40 video series. Everyday waking up with your videos make my day very active.... Thank you!
I like the way you teach us, Navin. I am learning a lot from your videos. From this video, I learned how to find Factorials of a number with just two lines of code using reduce. from functools import reduce print(reduce(lambda a, b: a * b, range(1, int(input("Enter a number: ")) + 1))) cool bro, really appreciate your help on learning python :)
Sir, all lambda functions are working similar(filter(),map(),reduce()). Then what is the main difference between them. Among three which function is better to use.
Very important video but please sir try to upload more videos daily. After uploading complete series please sir make some projects/softwares.. it will be very helpful to understand the real world problems 🙏🙏🙏..
After a long time, I finally understood the concept of Lambda, Reduce, Map function. Great video and well explained. Thank you so much sir. Now eager to learn more and more every day through your videos. Thank you so much, keep up the great work.
code --> from functools import reduce def adding(a,b): return a+b def update(n): return n*2 num=[1,2,3,4,5,6,7,8,9,10] even=list(filter(lambda x:x%2==0,num)) print(f"even numbers are {even}") double=list(map(lambda x:x*2,even)) print(f"double of all the even numbers {double}") sum=reduce(lambda x,y:x+y,double) sum=str(sum).center(10) print(f"the addition of all the numbers ae present in the double are {sum}")
if we have the list abc = [1,2,3,4] it will take the first two elements from the list and perform the function, the new list now becomes [3,3,4] the process is repeated till we have a single value
I have made a use of lambda and map() method and would like to share .. And here is the snippet : a,b=[int(x) for x in input("Enter two values seperated with spaces : ").split()] tup=( lambda c,d : c+d, lambda c,d : c-d , lambda c,d : c*d , (lambda c,d : (c+d)/2)) dic=dict(zip(('Sum' , 'Difference' , 'Product' , 'Average'),map(lambda x : x(a,b),tup))) for j in dic: print("{} : {}".format(j,dic[j])) Hope this gets useful in some way. Thank You :)
Hi Navin. Your videos are amazing. I am following your python series. I wanted to know from where did you learn the big data? I saw you said that you have learnt big data. Could you you please let me know the reference please? I want to learn big data.
numbs =[] n = int(input("Enter the number of elements you want to enter: ")) for i in range(n): a = int(input("Enter the value:")) numbs.append(a) evens = list(filter(lambda a : a%2==0,numbs)) print(evens)
nums =[1,2,3,4,5,6,7] evens = list(map(lambda n: n % 2 == 0,nums)) print(evens) if the function is a condition then it will give true or false according to the input output : [False, True, False, True, False, True, False]
navin sir i am very happy for your lectures, its very clear cut and good ...a request form my side to plan videos on problem solving python, which is used for placements for some lakhs of engineering students...i am expecting that one.
from functools import * numbs = [] n=int(input("Enter the number of value to be added:")) for i in range(n): a = int(input("Enter the value: ",)) numbs.append(a) result = reduce(lambda a,b : a+b, numbs) print(numbs) print(result)
list = [] n = int(input("Enter the number of elements you want to enter: ")) for i in range(n): a = int(input("Enter the value:")) list.append(a) if a % 2 == 0: print("It is an even number : ", a) else: print("it is an odd number") print(list)
taking input from user performed all the map reduce and filter hope it will help anyone from functools import reduce nums=[] n=int(input('enter the elements')) for i in range(0,n): ele=int(input()) nums.append(ele) even = list(filter(lambda n:n%2==0,nums)) print(even) double=list(map(lambda n:n*2,even)) print(double) sum=reduce(lambda a,b:a+b,double) print(sum)
What an interesting lesson. As always, enjoyed the lesson very much. I have a small problem. In this lesson, we assigned a list to the variable "doubles". in defining the function as well as when using lambda, we give two variables to take two parameters. So how does Python know which item in the list is which parameter? Also, how does it know after the doing the addition, the added number should be the first variable and the next number in the list should be the second variable. What is the logic behind this iteration? I tried to put myself in the Python's boots (even though it doesn't have legs) :-D but I couldn't. Can anyone offer me a helping hand?
The main challenge is when you are done studying and practising this and you continue with the course, someone forgets. and the query here Mr Navin is how can we interact often with these practices like say in some projects so that one knows why we are doing this, this can sink the point once.
# Program with Filter, Map & Reduce from functools import reduce nums = int(input("Enter the number of values, you want to enter in list: ")) a=[] for i in range(nums): x=int(input("Enter the number: ")) a.append(x) odd = list(filter(lambda n : n%2==1,a)) add = list(map(lambda n : n+4,odd)) redu = reduce(lambda a,b : a+b,add) print("The values provided as input is:", a) print("The odd values are: ", odd) print("The sum total of ODD values is: ", add) print("The reduce value is: ", redu)
Know what is the difference between filter, reduce and map:
map: Takes a function f, and a list L1, and returns a list L2 obtained by applying f to every element of L1. Say f is a function that takes x and returns 2x. Then, map(f, [1,2,3,4]) returns [2,4,6,8].
reduce: Takes a binary operator f, a list L and a seed value (or identity element). It returns the seed value if the list is empty. Otherwise, it applies the binary operator f to the seed and first element of L, then applies f to the result of this and the 2nd element of L, and so on till L is exhausted. The result is returned. This can be seen as a generalization of factorial function.
filter: Takes a boolean function f and a list L1. It applies the function to each element of L1, and list of those elements that give true is returned.
#insmot
Awesome
map function always returns an object.
One need to convert to list explicitly.
Thanks brother
didn't get about reduce function
Perfect
Finally found a cool programmeer who teaches these concepts in best possible way❤❤😇 Thanks navin sir
this is one of the best python tutorial series for begineers
and the main part is it is free thank you sir
Sir, you have made boring topics interesting for us..i love your teaching method..Great job!!
In case anyone need more information about the difference between filter, map and reduce:
Difference 1:
1. 'Map' takes all objects in a list and allows you to apply a function to it. The result is usually the same quantity of items as in the main list but with some execution(as specified in the function).
2. 'Filter' takes all objects in a list and runs that through a function to create a new list with all objects that return True in that function. Not necessary that it will output same number of items as present in the main list.
Difference 2:
1. In Map you can use multiple iterables definition : map(function_object, iterable1, iterable2,...)
2. Whereas in filter only one iterable can be used definition : filter(function_object, iterable)
Difference 3:
Further in filter the function_object has to return boolean only.
Hope it helps! :) #insmot
thanks a lot
Hey, Thanks for this clarification. but, you didn't mention the purpose of reduce function there :)
It's helpful
the form of steps u choose while teaching is unique and more understandable as compared to other lecturers thank u sir great explanation☺️
oh god! you are simply answering all the questions that pop my head. thank you navin. you have no idea what a great part you are holding in my life. because of you, im fearless and ready to learn programming. thank you for saving my life.
"that's what programmers do, making things cool" and how cool he looks with that action ;)
makkhan lagana band karo rre xD
@@harshwardhansingh617 lol
tum toh bare heavy driver ho
Lambda is my new crush ,😍😍❤️❤️
I love lambda
Indeed!
really pandey g,....i am also pandey............are u student??
finally found a good tutor who does'nt just dump all the codes and and leave logic behind completely making it boring and useless to watch.
really amazing sir.
Seriously your Python videos are amazing.
kudos to you
such a headache of lambda syntax clarified so simply. Thankx.
i was married to java and its version 8 features; after watching this i am planning to cheat in my relationship
you will be presented in the court if you do this :)
I will stay faithful to both
Ill treat java as a friend (friendzoned)
😝
😃
Java will divorce you
Navin sir can u make more videos and more concepts as soon as possible because we are understand very easy with ur explaination
NOTE : TRY TO MAKE SOME PROJECTS AND SOFTWARE USING THIS CONCEPTS
demanding huh.....
from functools import *
num = [2,4,5,6,7,8,9,1,0]
odds =(list(filter(lambda n: n%2!=0 ,num)))
square=(list(map(lambda a: a*a,odds)))
sum=(reduce(lambda x,y: x+y,square))
print(sum)
This is so amazing! I learnt a whole lot about not just lambda from this video, but also these three other useful (albeit advances) functions! Thank you so much!
You are a teacher of note ... not only a coder ... Thanks for the effort. If I can do anything to help you expand ( other than liking or subscribing ), let me know.
Thank you! Wishing you all the best 🙏🏼
Comparaing it with java in java we have to use -> operator here only : and also here we have to write lambda
Your smart explanation helps me to get out of my fear in learning python😍😍😍
Hello Sir,
Thanks so much for the lessons. I have coded factorial of a number using reduce functions. Its working:-)
from functools import reduce
s=[]
n=int(input("Enter the number"))
for i in range(n+1):
if i==0:
continue
else:
s.append(i)
print(s)
total = reduce(lambda a,b: a*b,s)
print(total)
Sir...your teachings are awesome and you are a blessing to a lot of new programmers
Many many thanks Navin for clearing the concept of Map Reduce. You are a gem. Super likes
So enjoyable your teaching skill. Really i am getting all this things free. Thanks sir great heads off.
Class Moniter could you please let me know whether this channel has videos on python and are they easy to understand? Thanks in advance.
"Hats off" is the expression
@@MegaCherry0 This is a reply after 7 months but I can confidently say that this is the best channel for python. I regret not discovering this channel earlier
SaFFire thank you so much buddy.
@@MegaCherry0 you're welcome. I'm 7 months late though 😅
"that's what programmers do, making things cool" ; thank you a lot Navin Sir
Than you sir, after working out this problem myself in laptop, this become simple now... You are a greater teacher and thanks for making me to sit here till above 40 video series. Everyday waking up with your videos make my day very active.... Thank you!
if we use for loop to seperate evens than it will take time complexcity o(n)..by using lambda what is the time complexicity
I like the way you teach us, Navin. I am learning a lot from your videos.
From this video, I learned how to find Factorials of a number with just two lines of code using reduce.
from functools import reduce
print(reduce(lambda a, b: a * b, range(1, int(input("Enter a number: ")) + 1)))
cool bro, really appreciate your help on learning python :)
Factorial!!!
I have watched so many tutorials and had no idea until i watch this masterpiece🎉
Love how you kept in your mistakes. Very honest.
Very helpful to me. It's crystal clear. Prior to watching this video I could not understand filter and map.
Legend says, the hardest part of programming is naming the variables.
Sir, all lambda functions are working similar(filter(),map(),reduce()).
Then what is the main difference between them.
Among three which function is better to use.
Navin you are a great teacher!
Very important video but please sir try to upload more videos daily. After uploading complete series please sir make some projects/softwares.. it will be very helpful to understand the real world problems 🙏🙏🙏..
You are the best.... no teacher ca teach like you
You are really a fabulous teacher
🤩🤩🤩
After a long time, I finally understood the concept of Lambda, Reduce, Map function. Great video and well explained. Thank you so much sir. Now eager to learn more and more every day through your videos. Thank you so much, keep up the great work.
Sir, Can you please start Machine learning with Python tutorial.
Sir this is very necessary
This is the Beauty of python.... And sir hats off for ur teaching
Your teaching technique is so lovely!!!
simple and clean Explanation
thank you sir
it's brief and clear .Thank you so much sir
After watching this video my all doubt got clear hats off to sir quality and method of teaching lit.. Tx
code -->
from functools import reduce
def adding(a,b):
return a+b
def update(n):
return n*2
num=[1,2,3,4,5,6,7,8,9,10]
even=list(filter(lambda x:x%2==0,num))
print(f"even numbers are {even}")
double=list(map(lambda x:x*2,even))
print(f"double of all the even numbers {double}")
sum=reduce(lambda x,y:x+y,double)
sum=str(sum).center(10)
print(f"the addition of all the numbers ae present in the double are {sum}")
Great Playlist for Python. I like it.
One doubt here, how a+b added all variables without using any loop?
if we have the list abc = [1,2,3,4]
it will take the first two elements from the list and perform the function, the new list now becomes [3,3,4]
the process is repeated till we have a single value
@@mohitsharma4667 for e.g , l = [2, 4, 6, 8]
>>> reduce(add_all, l)
2 + 4 --> 6
6(2 + 4) + 6 --> 12
12(6 + 6) + 8 --> 20
final sum: 20
that's how reduce() works! :)
you are awesome teacher ever ... And your teaching style is really energetic
Your explanation is very awesome. Thanks a lot!!
I saw you video after 2 months and editing level is whole different level. I got so much inspiration from you. thank you sir for making this video!!
Navin sir you are a legend 🙏🏻❣️
Thanks again
The next level of awesome teaching
Find average of list:
from functools import reduce
list = [1,2,3,4,5,6,7,8]
ave = reduce(lambda a,b: a+b,list)/len(list)
print(ave)
I thought your vids were useless at the first
but then I understood that your vids r very helpful
thank you soo much.
from functools import reduce
nums = [1,2,3,4]
odds = list(filter(lambda n:n%2==1,nums))
print(odds)
x = list(map(lambda n:5*n, odds))
print(x)
y = reduce(lambda a,b:a+b,x)
print(y)
Output
[1,3]
[5,15]
20
I have made a use of lambda and map() method and would like to share ..
And here is the snippet :
a,b=[int(x) for x in input("Enter two values seperated with spaces : ").split()]
tup=( lambda c,d : c+d, lambda c,d : c-d , lambda c,d : c*d , (lambda c,d : (c+d)/2))
dic=dict(zip(('Sum' , 'Difference' , 'Product' , 'Average'),map(lambda x : x(a,b),tup)))
for j in dic:
print("{} : {}".format(j,dic[j]))
Hope this gets useful in some way.
Thank You :)
This man is an absolute legend
this was the only tutorial I undestood about map filter an reduce
Hi Navin. Your videos are amazing. I am following your python series. I wanted to know from where did you learn the big data? I saw you said that you have learnt big data. Could you you please let me know the reference please? I want to learn big data.
numbs =[]
n = int(input("Enter the number of elements you want to enter: "))
for i in range(n):
a = int(input("Enter the value:"))
numbs.append(a)
evens = list(filter(lambda a : a%2==0,numbs))
print(evens)
u makes the concept understandable
4:03 best part of the Video
thank me later
😂😂😂😂🤣🤣🤣
🤣🤣
That scene was really funny
The way he said
😂
from functools import reduce
lst = [2,4,5,25,21,66]
evens = list(filter(lambda n : n%2==0,lst))
doubles = list(map(lambda n : n*2,evens))
sum = (reduce(lambda a,b : a+b,doubles))
print(evens)
print(doubles)
print(sum)
Great tutorial and by the way THANKYOU for making these videos AD FREE.
Sir your class is fantastic, more understandable
nums =[1,2,3,4,5,6,7]
evens = list(map(lambda n: n % 2 == 0,nums))
print(evens)
if the function is a condition then it will give true or false according to the input
output : [False, True, False, True, False, True, False]
navin sir i am very happy for your lectures, its very clear cut and good ...a request form my side to plan videos on problem solving python, which is used for placements for some lakhs of engineering students...i am expecting that one.
from functools import *
numbs = []
n=int(input("Enter the number of value to be added:"))
for i in range(n):
a = int(input("Enter the value: ",))
numbs.append(a)
result = reduce(lambda a,b : a+b, numbs)
print(numbs)
print(result)
Navin sir thank you soo much for this series...I learned alot from this series...it is very easy and helpful..thank you soo much for your efforts ☺️☺️
you are helping many people sir. keep going
sir , U r my hero shall i tell in my mother toungue,
Marana mass
Sorry to ask. Which language.?
@@allofmystuffs tamil
Thalaivar 🔥
Sir please start with python on these weekend it will help those people who are watching your python playlist
Awesome work sir and please make more videos like these and give us some projects and assignment 👍🏻💯
f=lambda a: a%2 ==0
>>> nums=[1,2,3,4,5,6,8]
>>> evens=list(filter(f,nums))
>>> print(evens)
[2, 4, 6, 8]
using lambda function..
Really awesome explanation about this topic, I really love it and understood very well by ur way of teaching...🙏❤️
it's 2024 still we are following your videos even though its 5 years ago B'coz of your excellent explanation and amazing programming
list = []
n = int(input("Enter the number of elements you want to enter: "))
for i in range(n):
a = int(input("Enter the value:"))
list.append(a)
if a % 2 == 0:
print("It is an even number : ", a)
else:
print("it is an odd number")
print(list)
Big Data concept is so relatable for me to understand this concept.❤❤
I like the way of u teaching sir superb...... 👌👌
i knew lamda function but filter ,map and reduce is useful for handling huge data ... so thanks for video
loved the method of your explaining
Sir, How can you describe so easily and understandably. Hats off Sir
Thank you so much the only tutorial that i can actually understand!! ♥♥
from functools import *
lst=[1,2,3,4,5,6,7,8,9]
even=list(filter(lambda n : n%2!=0,lst))
double=list(map(lambda i : i*2,even))
add=reduce(lambda a,b : a+b,double)
print(even)
print(double)
print(add)
perfectly explained thanks,,,was confused earlier
I really like the way you explain concepts❤
Hands down the best place to learn Python❤❤❤❤❤❤
Thank you very much. You are a genius.
Excellent explanation !!!
Wonderfully explained! Thanks.
Hey man tnx for your help I was really confused but now I find it out !!😍
taking input from user performed all the map reduce and filter hope it will help anyone
from functools import reduce
nums=[]
n=int(input('enter the elements'))
for i in range(0,n):
ele=int(input())
nums.append(ele)
even = list(filter(lambda n:n%2==0,nums))
print(even)
double=list(map(lambda n:n*2,even))
print(double)
sum=reduce(lambda a,b:a+b,double)
print(sum)
What an interesting lesson. As always, enjoyed the lesson very much.
I have a small problem.
In this lesson, we assigned a list to the variable "doubles". in defining the function as well as when using lambda, we give two variables to take two parameters. So how does Python know which item in the list is which parameter? Also, how does it know after the doing the addition, the added number should be the first variable and the next number in the list should be the second variable.
What is the logic behind this iteration? I tried to put myself in the Python's boots (even though it doesn't have legs) :-D but I couldn't. Can anyone offer me a helping hand?
he said that these functions are not easy, but I found them so easy : P
Very Nice explanation , Thank you
The main challenge is when you are done studying and practising this and you continue with the course, someone forgets. and the query here Mr Navin is how can we interact often with these practices like say in some projects so that one knows why we are doing this, this can sink the point once.
great presentation skills sir
# Program with Filter, Map & Reduce
from functools import reduce
nums = int(input("Enter the number of values, you want to enter in list: "))
a=[]
for i in range(nums):
x=int(input("Enter the number: "))
a.append(x)
odd = list(filter(lambda n : n%2==1,a))
add = list(map(lambda n : n+4,odd))
redu = reduce(lambda a,b : a+b,add)
print("The values provided as input is:", a)
print("The odd values are: ", odd)
print("The sum total of ODD values is: ", add)
print("The reduce value is: ", redu)
tnq so much for providing such necessary knowledge on python .plz sir make videos on advance python 😊
I'm 16 years old and I have learnt almost every language from you sir. You are such awesome tutor. ❤️❤️❤️
all things are clear but i really like comprehensions