Write Pythonic Code Like a Seasoned Developer Transcripts
Chapter: Pythonic Loops
Lecture: There is no numerical for loop

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0:01 Loops in Python are a little bit different than loops in other languages. You'll see that there is much more collections philosophy underlying them.
0:08 Let's start with the basics. There is no numerical loop in Python, there is no "for" loop, like C++, C#, Java, Javascript,
0:17 they have this way of walking through a number and incrementing it
0:20 usually to pull items out of an array, so I imagined what would that look like in Python
0:24 if we had a numerical "for" loop, something like: "this for i = 0; i less than len(data); i++ " we are going to go work with items.
0:31 Well, that doesn't exist. Sometimes, people try to work their way around it using the loops that do exist and recreating this more or less.
0:41 Look, we've done it, we've taken the initialization of the variable, moved before loop,
0:45 we have the test and now withing the body loop we do the increment. Perfect. No, technically that works but this is also super non-Pythonic
0:53 so let's look at some code that is. All right, here in PyCharm you can see I kind of sketched out
0:58 what that might look like, well as you saw we can well, first of all, this just put any ideas out of your head, this doesn't round right, obviously.
1:08 There is no "for" loop, but we can fake this idea we can say the "i = 0" goes here, this can be a "while" loop,
1:15 we can do our test there and this increment bit, we can put that down here. Like so, we don't have "++" but we do have a "+= 1", let's see if it works,
1:25 it should put out 1 and 7 then 11, oh but of course, it does not, let's do this. Now it prints out the index and it prints out the value.
1:37 All right, this is not Pythonic, so we'll just make a note: "No, NOT Pythonic". So of course, what is the proper way to loop through these items?
1:47 "for item in the collection" and let's print this out, instead of worrying about the index, we just have the item
1:56 let's put a new line in between, there: 1, 7, 11. Perfect. No fuss, no muss, just go.
2:06 So, there is no numerical "for" loop or faking it like this, also not Pythonic, we'll talk about what you can do when you really need that later,
2:15 but typically, write loops like this. OK, in a graphic, no numerical "for" loop,
2:21 instead just loop over the data, usually the goal is to get at the underlying items and some sequence anyway.

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