How do i find the size of a variable in python?
The answer, "Just use Show That answer does work for builtin objects directly, but it does not account for what those objects may contain, specifically, what types, such as custom objects, tuples, lists, dicts, and sets contain. They can contain instances each other, as well as numbers, strings and other objects. A More Complete AnswerUsing 64-bit Python 3.6 from the Anaconda distribution, with Python 3:
How do you interpret this? Well say you have a set with 10 items in it. If each item is 100 bytes each, how big is the whole data structure? The set is 736 itself because it has sized up one time to 736 bytes. Then you add the size of the items, so that's 1736 bytes in total Some caveats for function and class definitions: Note each class definition has a proxy Slotted instances start out with 48 bytes on their first element, and increase by 8 each additional. Only empty slotted objects have 16 bytes, and an instance with no data makes very little sense. Also, each function definition has code objects, maybe docstrings, and other possible attributes, even a Also note that we use
Also note that resizing lists (e.g. repetitively appending to them) causes them to preallocate space, similarly to sets and dicts. From the listobj.c source code:
Historical dataPython 2.7 analysis, confirmed with
Note that dictionaries (but not sets) got a more compact representation in Python 3.6 I think 8 bytes per additional item to reference makes a lot of sense on a 64 bit machine. Those 8 bytes point to the place in memory the contained item is at. The 4 bytes are fixed width for unicode in Python 2, if I recall correctly, but in Python 3, str becomes a unicode of width equal to the max width of the characters. And for more on slots, see this answer. A More Complete FunctionWe want a function that searches the elements in lists, tuples, sets, dicts, We want to rely on Classes, modules, and functions are singletons - they exist one time in memory. We're not so interested in their size, as there's not much we can do about them - they're a part of the program. So we'll avoid counting them if they happen to be referenced. We're going to use a blacklist of types so we don't include the entire program in our size count.
To contrast this with the following whitelisted function, most objects know how to traverse themselves for the purposes of garbage collection (which is approximately what we're looking for when we want to know how expensive in memory certain objects are. This functionality is used by For example, functions know quite a lot about the modules they are created in. Another point of contrast is that strings that are keys in dictionaries are usually interned so they are not duplicated. Checking for Whitelisted Types, Recursive visitorTo cover most of these types myself, instead of relying on the This sort of function gives much more fine-grained control over the types we're going to count for memory usage, but has the danger of leaving important types out:
And I tested it rather casually (I should unittest it):
This implementation breaks down on class definitions and function definitions because we don't go after all of their attributes, but since they should only exist once in memory for the process, their size really doesn't matter too much. How do you find the size of a variable?The size of a variable depends on its type, and C++ has a very convenient operator called sizeof that tells you the size in bytes of a variable or a type. The usage of sizeof is simple. To determine the size of an integer, you invoke sizeof with parameter int (the type) as demonstrated by Listing 3.5.
What is __ sizeof __ in Python?The Python __sizeof__() method returns the size of the object in bytes. The sys. getsizeof() method internally call's __sizeof__() and adds some additional byte overhead, e.g., for garbage collection.
How many bytes is a variable in Python?Typically, eight bytes are used for the Python floating type.
How do I print int size in Python?To get the length of an integer in Python:
Use the str() class to convert the integer to a string, e.g. result = str(my_int) . Pass the string to the len() function, e.g. len(my_str) . The len() function will return the length of the string.
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