| Re: [eigen] solve with and without check |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] solve with and without check
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Mon, 24 Aug 2009 14:34:13 -0400
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2009/8/24 Andrea Arteaga <yo.eres@xxxxxxxxx>:
>> Need to stress this: because of this unreliability, the current solve
>> isn't really the "safe way" that it's supposed to be.
>>
>> My humble opinion: we remove it for now (so solve becomes
>> non-checking) and at a later date, if/when we have triangular solvers
>> that can check for existence, we add it back as solveWithCheck.
>
> I agree with this solution. I think it actually is the best way.
> I only wanted to show that small conflict.
Sorry for the noise, I made a mistake.
Actually, the problem is NOT that the triangular solvers do not check
for existence.
By the time we call the triangular solvers, we are sure that the
triangular matrix that we pass to them is invertible, so that there's
no need to check for existence.
Actually our solve-with-check does more or less the right thing, it's
just that I don't know what formula to use for the precision level
that it uses. I guess i need to make experiments... *grumble* that
takes time
so i'm no longer advocating removing solve-with-check, only make it
have another name than just solve.
Benoit