Home Backend Development Python Tutorial What is the difference between append and extend in python

What is the difference between append and extend in python

Jun 20, 2019 pm 04:08 PM

What is the difference between append and extend in python

Look at the code first, and then explain the principle

What is the difference between append and extend in python

Principle:

The two methods of Lists extend and append looks similar, but is actually completely different. extend accepts a parameter, which is always a list, and adds each element in this list to the original list.

Here there are 3 elements in the list ('a', 'b' and 'c'), and use another one with 3 elements ('d', 'e' and 'f') list is expanded so there are 6 elements in the new list.

Append, on the other hand, accepts a parameter, which can be of any data type, and is simply appended to the end of the list. Here the append method is called with a list parameter containing 3 elements.

The original list containing 3 elements now contains 4 elements. Why 4 elements? Because the last element just appended is itself a list. Lists can contain any type of data, including other lists. This may or may not be the result you want. If your intention is to extend, don't use append

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