NAME¶
pyecm - Number factorization with the Elliptic Curve Method
SYNOPSIS¶
pyecm [
OPTIONS] [
FACTORS]...
DESCRIPTION¶
pyecm factors numbers using the Elliptic Curve Method (ECM). If FACTORS
is given, it will factor each one of these. Otherwise, it will factor from
standard input. You can type "exit" to quit pyecm at any time.
- -h, --help
- Get help using pyecm.
- --portion=num
- Does only part of the work for factoring, corresponding to
what fraction of the total work the machine is doing. Useful for working
in parallel. For example, if there are three machines: 1GHz, 1GHz, and
2GHz, print should be set to 0.25 for the 1GHz machines and 0.5 for the
2GHz machine. Implies -r and -v. -r is needed to avoid duplicating work
and -v is needed to report results.
- --ov=num
- Sets the value of the internal parameter ov, which
determines the trade-off between memory and time usage. Do not touch if
you do not know what you are doing. Please read all the documentation and
understand the full implications of the parameter before using this
switch.
- -n, --noverbose
- Terse. On by default. Needed to cancel the -v from the
--portion or --random switches. If both -n and -v are specified, the one
specified last takes precedence.
- -r, --random
- Chooses random values for sigma, an internal parameter in
the calculation. Implies -v; if you're doing something random, you want to
know what's happening.
- -v, --verbose
- Explains what is being done with intermediate calculations
and results.
EXAMPLES¶
- pyecm 2^3-1 1000 "(3^13+2)*5"
- Factor 7, 1000, then 7971625.
- pyecm
- Get factors from standard input.
AUTHOR¶
Written by Eric Larson and Martin Kelly.
REPORTING BUGS¶
Please send bugs to Eric Larson <elarson3@uoregon.edu>.