Below code demonstrates the difference between assignment, shallow copy using the copy method, shallow copy using the (slice) [:] and the deepcopy. Below example uses nested lists there by making the differences more evident.
A shallow copy constructs a new compound object and then (to the extent possible) inserts references into it to the objects found in the original. A deep copy constructs a new compound object and then, recursively, inserts copies into it of the objects found in the original.
To get a fully independent copy of an object you can use the copy.deepcopy() function. For more details about shallow and deep copying please refer to the other answers to this question and the nice explanation in this answer to a related question.
I am working with two files, and I need to copy a few lines from one file and paste them into another file. I know how to copy (yy) and paste (p) in the same file. But that doesn't work for different
When selecting a sub dataframe from a parent dataframe, I noticed that some programmers make a copy of the data frame using the .copy() method. For example, X = my_dataframe[features_list].copy() ...
copy copy.copy() copy.deepcopy() copy() is a shallow copy function. If the given argument is a compound data structure, for instance a list, then Python will create another object of the same type (in this case, a new list) but for everything inside the old list, only their reference is copied. Think of it like:
How do I copy a file in Python?copy2(src,dst) is often more useful than copyfile(src,dst) because: it allows dst to be a directory (instead of the complete target filename), in which case the basename of src is used for creating the new file; it preserves the original modification and access info (mtime and atime) in the file metadata (however, this comes with a slight overhead). Here is a ...
This answer explains copy by reference vs copy by value. Shallow copy vs deep copy is a concept that applies to collections. See this answer and this answer.
The copy module does not use the copy_reg registration module. In order for a class to define its own copy implementation, it can define special methods __copy__() and __deepcopy__(). The former is called to implement the shallow copy operation; no additional arguments are passed.
A copy constructor is a constructor which does deep copy. You should write your own copy constructor when there is a pointer type variable inside the class. Compiler will insert copy constructor automatically when there is no explicit copy constructor written inside the code. The type of a copy constructor parameter should always be reference type, this to avoid infinite recursion due to the ...
