| Re: [eigen] Memory fault when using a function returning a SelfAdjointView |
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On 26.10.2011 21:52, Douglas Bates wrote:
It certainly requires redundant code, but even with basic code optimizations
there should be no overhead due to that.
I wasn't concerned about overhead as much as creating more readable code.
Yes, I agree. The only thing I could suggest is sth like:
// calculate matrix:
MatrixXd mat = XtXmat(...);
// use only xtx after that:
SelfAdjointView xtx(mat);
You can't entirely avoid the separate declaration of a plain matrix,
because somewhere the actual data has to be stored.
BTW:
MatrixXd(cols, cols).setZero() == MatrixXd::Zero(cols, cols).
I don't think so - at least in my testing it didn't. That problem is
that MatrixXd::Zero returns a constant matrix and I want to modify it.
Yes, you are right. Actually I was wondering, if rankUpdate() on a
ZeroMatrix is automagically optimized to basically just X.transpose()*X
(evaluating just one half), but apparently it does not work anyways.
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