Python Tuples

Quick reference

• 00:05 Okay, in this video I want to talk about tuples.
• 00:07 And tuples are basically the same thing as lists.
• 00:09 They're nearly identical.
• 00:11 The only real difference is a tuple can't be changed.
• 00:14 Once a tuple is created, you can't add to it, you can't remove,
• 00:17 you can't change it in any way.
• 00:19 Except you sort of can, we'll talk about that as we go on here.
• 00:22 So we haven't talked about it yet, but in the future,
• 00:25 we're going to be connecting our Python programs to our Excel spreadsheets
• 00:29 using something called openpyxl.
• 00:31 And sometimes openpyxl returns things as tuples,sometimes it returns them as lists.
• 00:36 So we need to be familiar with what a tuple is at least, and
• 00:38 that's what we're going to talk about in this video.
• 00:41 So let's create a tuple, but first, let me create a list.
• 00:44 And I'm going to create a list called names.
• 00:47 And just like we learned in the last video, we can go 'John', and
• 00:51 'Mary', let's go T'im'.
• 00:54 So we've got this list called names.
• 00:56 And if we want to print this out, we can print names.
• 00:59 And we learned how to do this already in the last video.
• 01:01 So the difference between a list and a tuple is these brackets, so
• 01:05 a list has square brackets.
• 01:09 A tuple has parentheses, and really that's the only difference.
• 01:12 So now this is a tuple, right?
• 01:15 So it's sort of weird, but this is really the only difference.
• 01:19 And we can print it out just like we did with a list.
• 01:22 So if we go ahead and save this, and head back over to our terminal.
• 01:27 And we can run this guy.
• 01:28 We get John, Mary, Tim, and you notice the parentheses around it.
• 01:33 So even the Python interpreter knows that this is a tuple.
• 01:36 If we were to come back here and change this back to a list,
• 01:41 and then save this and run it.
• 01:47 I can see now the square brackets are outputs.
• 01:50 So just remember parentheses means tuple, square brackets means list.
• 01:55 So, okay, let's change this back to a tuple now.
• 02:00 And how do we access the things inside of our tuple?
• 02:03 Just the exact same way as we did with a list.
• 02:06 And again, these are numbered just like a list.
• 02:08 So the first item is zero.
• 02:10 Second item is one.
• 02:11 The third item is two.
• 02:12 So zero, one, two.
• 02:14 And we access them in the exact same way with these square brackets.
• 02:18 Now, this is kind of weird, right?
• 02:19 You would think that we would do something like this, since tuples have parentheses.
• 02:24 But no, we still use the square brackets.
• 02:28 Which is kind of weird, but that's how this goes.
• 02:30 So go ahead and save this and let's run this.
• 02:34 And it prints out John.
• 02:36 I mentioned earlier that the main difference between a tuple and
• 02:40 a list besides the parentheses, are that you can't change a tuple.
• 02:43 Tuples are immutable.
• 02:45 They can't be added to or you can't remove things from them.
• 02:48 Except you sort of can if you hack around a little bit, so we can,
• 02:51 let's rename this to names_1.
• 02:53 Let's create another tuple.
• 02:54 And we'll call it names_2.
• 02:56 And inside of here, let's add Bob.
• 03:00 And one weird thing about a tuple is when you only have one item,
• 03:03 you still have to put a comma as if there were other items.
• 03:07 So we've got names_1 and names_2.
• 03:10 Now we can create a third tuple, let's call it names_3.
• 03:15 And set that equal to names_1 + names_2.
• 03:20 So we can add the first tuple to the second tuple.
• 03:23 And it's not actually adding them it's putting them together, right?
• 03:27 And so then our third one becomes John, Mary, Tim and Bob.
• 03:31 So if we were then to come down here and print out names_3,
• 03:37 if we go ahead and save this and run it.
• 03:40 We see John, Mary, Tim, and Bob.
• 03:43 So technically, did we change this first tuple?
• 03:47 No, but if we wanted to add a name to this tuple, we could just do it this way.
• 03:53 And then now we have a new table called names_3.
• 03:55 If we then wanted to rename names_3 names_1, we could and then hey,
• 03:59 we've changed our first tuple.
• 04:02 I mean, technically we haven't.
• 04:03 But for all intents and purposes we have.
• 04:05 So there's always ways with coding to hack around things and
• 04:08 get around rules if you need to.
• 04:10 So I'm not sure we're actually ever going to use this in this course, but
• 04:12 it's kind of a fun thing to learn.
• 04:14 And something interesting about tuple.
• 04:16 So those are tuples.
• 04:18 Like I said, we're going to be getting data from our Excel spreadsheets in
• 04:21 the form of lists and tuples.
• 04:23 So it's a good idea that we just understand at least what they are.
• 04:26 And I think we've done that in the last couple of videos.
• 04:28 We really don't need in depth knowledge of these things.
• 04:32 We just need a basic understanding of them.
• 04:33 And I think we've got that now.
• 04:34 So in the next video, we'll look at for loops.
• 04:37 And then after that, we'll start to look at openpyxl.

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