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ProjetPP / PPP-CAS

Computer Algebra System module for the Projet Pensées Profondes
MIT License
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999999999^9999999^999^99^999^99999 returns an error #17

Open Tpt opened 9 years ago

Tpt commented 9 years ago

Not sure of what we should do on such big inputs

marc-chevalier commented 9 years ago

Not my fault! Sympy tries to do the computation since it knows it will succeed but it is killed by timeout of the subprocess. There is not way to predict if a computation will be long. If you disagree, think about the halting problem. So, we cannot do anything. I think the best is just to consider this input as "I cannot handle it", just as when the input is not a mathematical formula and to return... nothing.

Le 02/02/2015 17:20, Thomas Tanon a écrit :

Not sure of what we should do on such big inputs

— Reply to this email directly or view it on GitHub https://github.com/ProjetPP/PPP-CAS/issues/17.

Marc Chevalier

ENS de Lyon Site Monod M1 Informatique Fondamentale

Tpt commented 9 years ago

Yes, I agree that it is difficult. I've opened this issue thinking more "we should track this issue" than "we should solve this issue now".

marc-chevalier commented 9 years ago

I think there is nothing to do. Or add a error message saying "Oups! Too long computation, sorry. Do it yourself or buy Mathematica" But the doesn't change really anything.

eddycaron commented 9 years ago

True. You should have at least a timeout to decide when you cancel the computation. Just one way to avoid malicious guys who try to stress platypus for bad reason.

Eddy Caron. Mcf HDR ENS Lyon ENS Lyon - LIP - Projet AVALON E-Mail : Eddy.Caron@ens-lyon.fr

[http://graal.ens-lyon.fr/~ecaron]

Le 2 févr. 2015 à 18:01, Marc Chevalier notifications@github.com a écrit :

I think there is nothing to do. Or add a error message saying "Oups! Too long computation, sorry. Do it yourself or buy Mathematica" But the doesn't change really anything. — Reply to this email directly or view it on GitHub.

marc-chevalier commented 9 years ago

We have a timeout for a long time, almost before the first deployement. https://github.com/ProjetPP/PPP-CAS/blob/master/ppp_cas/evaluator.py#L25

Le 02/02/2015 18:08, eddycaron a écrit :

True. You should have at least a timeout to decide when you cancel the computation. Just one way to avoid malicious guys who try to stress platypus for bad reason.

Eddy Caron. Mcf HDR ENS Lyon ENS Lyon - LIP - Projet AVALON E-Mail : Eddy.Caron@ens-lyon.fr

[http://graal.ens-lyon.fr/~ecaron]

Le 2 févr. 2015 à 18:01, Marc Chevalier notifications@github.com a écrit :

I think there is nothing to do. Or add a error message saying "Oups! Too long computation, sorry. Do it yourself or buy Mathematica" But the doesn't change really anything. — Reply to this email directly or view it on GitHub.

— Reply to this email directly or view it on GitHub https://github.com/ProjetPP/PPP-CAS/issues/17#issuecomment-72494924.

Marc Chevalier

ENS de Lyon Site Monod M1 Informatique Fondamentale

marc-chevalier commented 9 years ago

Moreover, I'm pretty sure the timeout works because, since we use platypus-angel which is less powerful as the previous server, the request "Integrate[Sin[x*y], {x, 0, 1}, {y, 0, x}]" (one of my longer test) caused an error until we increase the timeout. Since, that works again correctly.