| Re: [eigen] still the solve() API debate |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] still the solve() API debate
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Fri, 11 Sep 2009 10:49:40 -0400
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2009/9/11 Robert Bocquier <robert.bocquier@xxxxxxxxxxx>:
> Well, I don't fully understand this thread, so may be I will say something
> stupid, but I found these "asymmetric" writing of swap pretty unreadable.
Nevermind, we're not going to use them anyway :)
> Why is this impossible ?
> Eigen::swap(matrix.row(i), matrix.row(j));
Same reason as above: one can't pass matrix.row(i) as non-constant
reference (because it is a temporary) so one must pass it as constant
reference, and then constness can't be honored. So this is possible
but has the same drawback as the current implementation, actually it's
a bit worse even because it forgets constness of both sides instead of
just the right-hand side.
Actually my first proposal,
matrix.row(i) = Eigen::swap(matrix.row(j));
doesn't work either.
So my only potential proposal was:
matrix.row(i) = matrix.row(j).swap();
and you're already 2 persons to reject it, so let's forget about it :)
Benoit