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Set the Python file maximum line length to 88 characters (#2122)

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* flake8 --max-line-length=88

* fixup! Format Python code with psf/black push

Co-authored-by: github-actions <${GITHUB_ACTOR}@users.noreply.github.com>
This commit is contained in:
Christian Clauss
2020-06-16 10:09:19 +02:00
committed by GitHub
parent 9438c6bf0b
commit 9316e7c014
90 changed files with 473 additions and 320 deletions
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hashes/sdbm.py
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@ -1,13 +1,17 @@
"""
This algorithm was created for sdbm (a public-domain reimplementation of ndbm) database library.
It was found to do well in scrambling bits, causing better distribution of the keys and fewer splits.
This algorithm was created for sdbm (a public-domain reimplementation of ndbm)
database library.
It was found to do well in scrambling bits, causing better distribution of the keys
and fewer splits.
It also happens to be a good general hashing function with good distribution.
The actual function (pseudo code) is:
for i in i..len(str):
hash(i) = hash(i - 1) * 65599 + str[i];
What is included below is the faster version used in gawk. [there is even a faster, duff-device version]
The magic constant 65599 was picked out of thin air while experimenting with different constants.
What is included below is the faster version used in gawk. [there is even a faster,
duff-device version]
The magic constant 65599 was picked out of thin air while experimenting with
different constants.
It turns out to be a prime.
This is one of the algorithms used in berkeley db (see sleepycat) and elsewhere.
@ -18,7 +22,8 @@
def sdbm(plain_text: str) -> str:
"""
Function implements sdbm hash, easy to use, great for bits scrambling.
iterates over each character in the given string and applies function to each of them.
iterates over each character in the given string and applies function to each of
them.
>>> sdbm('Algorithms')
1462174910723540325254304520539387479031000036