Cones and FACETS, EQUATIONS

[simon]

Hi there,

I've got another beginner's question: If I define a rational Cone, say the two-dimensional cone

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$c = new Cone(INPUT_RAYS=>[[1,0,0],[1,0,1]]);

and I want to compute both, its defining inequalities and its defining equations (such that c is the intersection of halfspaces and hyperplanes), I just know about

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print $c->FACETS;

which gives

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1 0 -1 0 0 1

but $c->EQUATIONS; just produces a waring "WARNING: available properties insufficient to compute EQUATIONS".
Surely, I'm doing something wrong?

[herr]

You are on the right track, but EQUATIONS is an input property (like INEQUALITIES, INPUT_RAYS, or INPUT_LINEALITY). The defining equations are stored in LINEAR_SPAN (and the defining inequalities are stored in FACETS).

[simon]

Thanks! (I assumed LINEAR_SPAN would give the linear hull )