Segfault sampling from HPolytope in R

[michiexile]

Describe the bug R segfaults when trying to draw random points from a randomly generated 5-dimensional HPolytope.

To Reproduce Steps to reproduce the behavior:

1. Instantiate an HPolytope with the following data:

             [,1]        [,2]         [,3]        [,4]        [,5]              
 [1,]  0.30887097 -0.53745122 -0.492380167 -0.49002472  0.36494173              
 [2,]  0.14248736  0.64991717 -0.704343633  0.19163703 -0.15646189              
 [3,]  0.03498200  0.63144837  0.419923300  0.05289024  0.64878059              
 [4,]  0.30949255  0.54458693 -0.476339377  0.27792713 -0.55090539              
 [5,]  0.04423147  0.40892918  0.511683391  0.75062985 -0.07453479              
 [6,] -0.41749508  0.34459983 -0.793759276 -0.17988560 -0.21103602              
 [7,] -0.64373902  0.33605519 -0.352343366 -0.49704459  0.31854011              
 [8,] -0.52725465 -0.20167977  0.450931987 -0.58732301  0.36474624              
 [9,]  0.80713044 -0.35137439  0.234729396 -0.26424122 -0.31647303              
[10,]  0.06392698 -0.10807311 -0.569276249 -0.65656141  0.47862846              
[11,] -0.37563325  0.80767531  0.005149686  0.45330771 -0.03233987              
[12,] -0.13155983 -0.13962400  0.015456808  0.88805782  0.41750635              
[13,]  0.58990541 -0.19920504  0.252185961 -0.44746159 -0.59034679              
[14,] -0.72467774  0.08202631  0.406466437 -0.54512009  0.07578241              
[15,]  0.26152950  0.35885079 -0.363057023 -0.66744716 -0.47490243              
[16,] -0.69317051  0.34747910  0.618674006  0.12349000  0.02766974              
[17,] -0.38584133 -0.10489989  0.632718077  0.02886336  0.66253847              
[18,]  0.78736884 -0.51983923  0.096110362  0.27149465  0.16392357              
[19,] -0.61112221 -0.23311823 -0.361741498  0.49155191 -0.44688404              
[20,] -0.62956211 -0.23468319 -0.516540178 -0.11050009 -0.51918332              
[21,]  0.31090258  0.71762591 -0.212720057 -0.28033834 -0.51430850              
[22,] -0.69102110  0.65821644 -0.273379940  0.09795671 -0.07006324
[23,]  0.21954957  0.58599794 -0.105495985 -0.58460572  0.50548111
[24,] -0.06008136 -0.31607680  0.210493804  0.86199031 -0.33037969
[25,]  0.06828425 -0.40678357 -0.280687167  0.16822021 -0.85016532

2. Sample random points from this polytope.

Expected behavior Generate random points.

Screenshots If applicable, add screenshots to help explain your problem.

Desktop (please complete the following information):

• OS: Ubuntu

Additional context Add any other context about the problem here.

[Ayantik2002]

Hi I would like to take up this issue but I am unable to get the R commands for initializing the polytope. Could you please refer me to the relevant document? Also please point me to the relevant section of the codebase where I should be looking at.

[michiexile]

Trying to recreate a minimal working example, it seems like I did not manage to extract all the defining data for an HPolytope from the crashing computations.

[vissarion]

@michiexile thanks for opening this issue. Could you please give more information about your input? I cannot reproduce as is. You are mentioning that you have a 5-dimensional Hpolytope but you are providing a 5x25 matrix which defines a 4-dimensional HPolytope. What is matrix A, b? Which function did you use to generate the polytope? Please refer to the documentation of the R interface here: https://cran.r-project.org/web/packages/volesti/volesti.pdf

[NehaAr]