Partial results from FACETS

[DennyDahl]

I'm attempting to compute the FACETS for a polytope.
The computation is currently ongoing and I have no indication when it will end.
So far I've expended about four CPU days.
The memory image of the process has been stable at <900 Mbytes for a few days.
Is it possible to get partial results from the computation in the event that it does not finish?
It would be useful for me to obtain a partial listing of the facets, even if the listing is not guaranteed to be complete.
The entire program is quite simple:

$p = porta2poly("unit_cell_L4.poi");
print $p->FACETS;

The polytope consists of 256 points in a 24-dimensional space.
Am I being unrealistic to expect this computation to complete?
Thanks,
-Denny

[joswig]

Unfortunately, the current setup does not allow for much logging information for the convex hull computations. I clearly understand that this is desirable though. We started to look into some possibilities. Stay tuned.

We do not allow partial output. This has to do with the overall design of polymake. We rather do not want to change this. However, lrs can continuously churn out facets (if points are the input), albeit repeatedly in general. This might be suitable for your needs.

How long the computation should take is very hard to predict. As one point of reference:

Code: Select all

polytope > print upper_bound_theorem(24,256)->F_VECTOR->[23]; 74101631980364157312

This is the maximum number of facets you might have (according to McMullen's Upper-Bound-Theorem). Without extra information there is not much more that can be said.