


Introduction to Python learning. With lists, why are there tuples?
python video tutorialThe column introduces why there are tuples
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There is a basic data structure in Python called tuple, but generally few people will use it, because during the development process, lists (list) can basically meet our needs.
Even so, you must not think that tuples are redundant. Otherwise, you won’t often be asked in interviews, what is the difference between tuples and lists? Why do you need tuples?
The following two points, the first point is well known to everyone, and the second point may only be known by experienced drivers. Only by learning the second point can we truly understand the value and significance of the existence of tuples. .
1. Immutable list
This is the most significant feature of tuples that distinguishes them from lists.
list: mutable sequence
tuple: immutable sequence
So what is an immutable sequence?
That is, after the tuple object is generated, functions such as inserting elements, deleting elements, adding elements, clearing elements, modifying elements, etc. are not available in the tuple, and you cannot modify them. .
Since tuples are immutable, their methods are also very limited. List them here.
2. Named tuple
This feature, I personally think, is the meaning of the existence of tuples.
Only talks about named tuples, which may not be easy to understand. If you call it a record with field names, you may understand.
Here is an example, but to implement field names, you need the support of a library (collections), and you need to import it.
It looks a bit like a dictionary, right? But it is not a dictionary (the method of obtaining values is also different from that of a dictionary). The dictionary is variable. Once a tuple is created, it cannot be modified. This shows to some extent that tuples are suitable for storing data that does not need to be modified. For example, above, place name, country, longitude and latitude.
In addition to the above usage, here we also introduce some unique properties of tuples.
# As a language that is constantly developing and popularizing, Python is still being updated. When studying, it is recommended to find some study partners to study and discuss together for better results. If you want to learn Python, you are welcome to join the Python learning exchange group (627012464) to supervise and learn together. It contains development tools, a lot of useful information and technical information to share!
To summarize, tuples are a very powerful data type that can be used as records. This is the value and significance of its existence. As we all know, its second role is to act as an immutable list. (The above are all personal opinions. If you have different opinions, please leave a message for discussion)
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