Python for Entrepreneurs Transcripts
Chapter: Appendix: Python language concepts
Lecture: Concept: Tuples
0:01 Tuples are a lightweight, immutable data structure in Python
0:04 that's kind of like a list but that can't be changed once you create them.
0:07 And you'll see many very cool techniques that make Python readable
0:11 and easy to use are actually clever applications of tuples.
0:16 On the first line here, we are defining a tuple m,
0:19 the way you define a tuple is you list out the values and you separate them by commas.
0:23 When you look at it, it appears like the parenthesis are part of the definition,
0:27 and when you print tuples you'll see that the parenthesis do appear
0:31 but it's not actually the parenthesis that create them, it's the commas.
0:35 We want to get the value out over here we want to get the temperature,
0:37 which is the first value, we would say m, so zero-based index into them.
0:41 If we want the last value, the fourth one,
0:44 we would say m, that's the quality of the measurements.
0:47 Notice below we are redefining m, this time without the parentheses,
0:50 just the commas and we print it out and we get exactly the same thing again,
0:54 so like I said, it's the commas that define the tuple not the parentheses,
0:58 there is a few edge cases where you will actually need to put the parentheses
1:01 but for the most part, commas.
1:04 Finally, tuples can be unpacked,
1:07 or assigned to a group of variables that contain the individual values.
1:11 So down here you can see we have a "t" for temperature,
1:15 "la" for latitude "lo" for longitude, and "q" for quality,
1:19 and those are the four measurements in our tuple,
1:22 we want to assign those and instead of doing like we did above
1:24 where you index each item out and assign them individually,
1:27 we can do this all in one shot, so here we can say variable,
1:32 four variables separated by commas equals the tuple,
1:34 and that reverses the assignment so you can see "t" has the right value of 22,
1:39 latitude 44, longitude 19 and the quality is strong.