Update time complexity in update.rst #46
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The time complexity of dictionary update is linear, i.e. O(N). The C implementation of Python dictionary does resizing, hasing and deleting in an amortized O(1) time. So, the update method, which uses the C implementation of the dict_merge() function as source, uses a for loop to update the dictionary. Sources: https://hg.python.org/cpython/file/tip/Objects/dictobject.c https://archive.org/details/pyvideo_276___the-mighty-dictionary-55 https://stackoverflow.com/questions/20906435/does-dictionary-do-resize-when-we-delete-an-item https://stackoverflow.com/questions/52504598/time-complexity-of-python-dictionary-get-update-always-o1
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The time complexity of dictionary update is linear, i.e.$O(N)$ . The C implementation of Python dictionary does resizing, hasing and deleting in an amortized $O(1)$ time. So, the update method, which uses the C implementation of the
dict_merge()function as source, uses a for loop to update the dictionary.Sources:
https://hg.python.org/cpython/file/tip/Objects/dictobject.c
https://archive.org/details/pyvideo_276___the-mighty-dictionary-55
https://stackoverflow.com/questions/20906435/does-dictionary-do-resize-when-we-delete-an-item
https://stackoverflow.com/questions/52504598/time-complexity-of-python-dictionary-get-update-always-o1