up previous next
|
FactorINT --
find prime factors of an integer
|
FactorINT(N: INT): RECORD
FactorINT_TrialDiv(N: INT, MaxPrime: INT): RECORD
FactorINT_PollardRho(N: INT, Niters: INT): RECORD |
These functions find small (usually prime) factors of an integer.
FactorINT
may take a very long time, and may produce only a partial factorization!
FactorINT_TrialDiv does trial division by all primes up to
MaxPrime;
be wary of giving large values for
MaxPrime.
FactorINT_PollardRho performs up to
Niters iterations of the Pollard-Rho algorithm;
the iterations stop as soon as a (non-trivial) factor is found. If no factor
was found, the result is an empty factorization. Note that the factor
found may not be prime! Be wary of specifying large values for
Niters.
From version 5.0.4, to comply with the naming conventions, the fields are
called
factors and
multiplicities instead of
Factors
and
Exponents.
/**/ FactorINT_TrialDiv(100,3);
record[factors := [2], multiplicities := [2], RemainingFactor := 25]
/**/ FactorINT(123456789);
record[factors := [3, 3607, 3803], multiplicities := [2, 1, 1], RemainingFactor := 1]
|