What's this code means?

Question

a=int(input('enter a num'))
b=[x for x in range (2,a) if a%x==0] #this

Answer 1

@Shubham... I really like your approach to break it apart in this format.

Expanding on this, I would clarify this further as:

new_list = [ (expression: to append using current value) for (the current value) in (collection) (where: some condition is true) ]

This is equivalent to the following:

new_list = []
for (the current value) in (collection):
if (some condition is true):
new_list.append(expression: using current value)

- The (expression) part could be the current value or an expression that modifies the current value.

- The (where) part is optional and could be zero or more if statements or for loops.

Your version is nicely condensed. I just wanted to expand with additional clarifications.

Answer 2

here LIST COMPREHENSION is used with list 'b' whose expression is as below:

b = [ (expression) for (value) in (collection)]

this is epuivalent to a for loop as if :

b = []
for (value) in (collection) :
b.append(expression)

Answer 3

Let's look at it this way

b = [x for x in range (2,10) if 10%x==0]

the range function returns a list like this [2, 3, 4, 5, 6, 7, 8, 9]

The "for" loop goes through the whole list number by number and stores it to the x variable

"for" loop goes 8 times (from 2 to 9) and if 10 divided with the number goes even it adds it to the list.

result will be b = [2, 5]

But in your code the number will be given by the user.

Answer 4

thank you