primefactors(n): an iterator on the primes that evenly divide n (repeating such as the product is n
(I don't have a good name): something telling that an integer can be represented exactly as a float On 12 July 2018 at 12:55, Serhiy Storchaka <storch...@gmail.com> wrote: > What are your thoughts about adding a new imath module for integer > mathematics? It could contain the following functions: > > * factorial(n) > > Is just moved from the math module, but non-integer types are rejected. > Currently math.factorial() accepts also integer floats like 3.0. It looks > to me, the rationale was that at the time when math.factorial() was added, > all function in the math module worked with floats. But now we can revise > this decision. > > * gcd(n, m) > > Is just moved from the math module. > > * as_integer_ration(x) > > Equivalents to: > > def as_integer_ration(x): > if hasattr(x, 'as_integer_ration'): > return x.as_integer_ration() > else: > return (x.numerator, x.denominator) > > * binom(n, k) > > Returns factorial(n) // (factorial(k) * factorial(n-k)), but uses more > efficient algorithm. > > * sqrt(n) > > Returns the largest integer r such that r**2 <= n and (r+1)**2 > n. > > * isprime(n) > > Tests if n is a prime number. > > * primes() > > Returns an iterator of prime numbers: 2, 3, 5, 7, 11, 13,... > > Are there more ideas? > > _______________________________________________ > Python-ideas mailing list > Python-ideas@python.org > https://mail.python.org/mailman/listinfo/python-ideas > Code of Conduct: http://python.org/psf/codeofconduct/ > -- <https://www.machinalis.com/> Daniel Moisset Technical Leader A: 1 Fore St, EC2Y 9DT London <https://goo.gl/maps/pH9BBLgE8dG2> P: +44 7398 827139 <+44+7398+827139> M: dmois...@machinalis.com <dmois...@machinalis.com> | S: dmoisset <http://www.linkedin.com/company/456525> <http://www.twitter.com/machinalis> <http://www.facebook.com/machinalis> <https://www.instagram.com/machinalis.life/>
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