equal_polyhedra

[satya123999]

Dear polymake team,

I import the following set of inequalities (in lp format)

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Maximize Subject To c0: - a1 = 0 c1: a1 - a2 = 0 c2: a1 - a3 = 0 Bounds a1 free a2 free a3 free End

then when I execute the following commands, it doesn't return 1 ?
$f = convert_to<Rational>lp2poly('file.lp');
print equal_polyhedra($f,$f);

Regards,
Satya

[blorenz]

Hello Satya,

thank you very much for your bug report. The problem turned out to be very subtle and somewhat deep inside the polymake code. We have fixed the problem for the upcoming release 2.14, scheduled around February.

A quick workaround for you is to edit apps/polytope/rules/lp_float.rules and move line 72 (\( \texttt{\$P->INEQUALITIES = \$Mineq;} \)) below line 86 (\( \texttt{\$P->EQUATIONS = \$MEq;} \)).

Best regards,
Benjamin

[satya123999]

Dear Benjamin,

I am curretnly having polymake version 2.12, So, untill I update to the 2.14 polymake next month, Can you please suggest changes in 2.12 version ?

Regards,
Satya

[blorenz]

Hello Satya,

for polymake 2.12 the corresponding change would be to switch lines 45 and 46 in apps/polytope/rules/lp_float.rules. Change it from

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$P->INEQUALITIES=new SparseMatrix<Float>($parser->Ineq); $P->EQUATIONS=new SparseMatrix<Float>($parser->Eq);

to

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$P->EQUATIONS=new SparseMatrix<Float>($parser->Eq); $P->INEQUALITIES=new SparseMatrix<Float>($parser->Ineq);

But I cannot test whether this works because I do not have a working 2.12 installation right now.

Benjamin

[satya123999]

Thank you , it works