|Re: [eigen] Commenting issue #110, disabling operator for matrices|
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- Subject: Re: [eigen] Commenting issue #110, disabling operator for matrices
- From: Márton Danóczy <marton78@xxxxxxxxx>
- Date: Thu, 22 Apr 2010 14:39:25 +0200
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In my opinion matrix(i) should be disallowed as well, I'd guess in
most of the cases matrix(i) means that the user mistakenly believes
the matrix to be a vector. I'd go for the more verbose but
Just my two cents.
On 22 April 2010 14:34, Benoit Jacob <jacob.benoit.1@xxxxxxxxx> wrote:
> here we are discussing disabling operator on matrices.
> We can perfectly disable it on matrices while keeping it on vectors
> (e.g. with a static assertion).
> The motivation for disabling it on matrices is to guard against this
> dreadful c++ code:
> which in c++ compiles as
> which addresses the i-th entry in the storage order of the matrix.
> If you want that functionality, there still is the synonym
> And the method coeff(int) if you want to avoid the assertion.
> People have already proposed adding an expression to view a matrix as
> a vector, following its storage order. But you can already do that
> with Map. If you really want, we can add a conveniene method
> asVector() to return such a Map object. But given the possibility of
> doing matrix(index), i don't see too much motivation for that...