mpz_root aborts for n-th root when n is very large
Torbjorn Granlund
tg at gmplib.org
Sun Feb 27 21:51:19 CET 2011
Marc Glisse <marc.glisse at inria.fr> writes:
... the function mpn_rootrem(_internal) indeed calls TMP_ALLOC_LIMBS
with an argument linear in k.
OK, computing a high root of 1 will ask for undue of memory.
I'd claim that computing the nth root of x, x < 2^n is somewhat strange,
since the result is always 1.
For x >= 2^n, the memory need is suddenly O(n) which isn't unreasonable.
Do you agree?
Now, should we do something about this? Should we check x < 2^n,
i.e. log(x) < n?
--
Torbjörn
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