Interesting. Now that's a compelling use case.

On Wed, Feb 12, 2014 at 3:41 PM, Jason Pries <[email protected]> wrote:

> FWIW, The place I use this the most is when solving PDEs using finite
> elements with Dirichlet/Periodic boundary conditions. If I want to preserve
> the symmetry of the matrix before factorization, I end up needing to delete
> some rows and columns. I could write the code to create the matrix the way
> I end up using it, but that would require every function that creates a
> matrix to know about the boundary conditions which complicates things
> considerably.
>
> In Julia, I would be using SparseMatrixCSC, so the issue is different than
> for general N-dimensional tensors. It's probably possible implement this
> functionality for SparseMatrixCSC using the existing functionality for
> vectors.
>
>
> On Wednesday, February 12, 2014 8:04:24 AM UTC-5, Andreas Lobinger wrote:
>>
>> Hello colleagues,
>>
>> i couldn't track down, where the Nonsense applies, but in general (also
>> in Matlab) it's better for organizing the data in a fixed array and track
>> down, what you access from that. This helps the computer/language system.
>>
>> However, it's not fully uncommon to formulate algorithms that
>> reduce/consume an array in an iterative way and it's just easier to read,
>> if the non-content is discarded. So this helps the reader or author of
>> software.
>>
>> Implementation for the first is straight forward.
>> Implementation for the second is (and will be) under discussion as
>> general CS topic...
>>
>>

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