Scratch that; I misread your request as I was forwarded a link to this with 
the title "Big SVD".

You should look into wrapping Elemental's HermitianEig and/or the 
appropriate routine from ELPA, unless you only want a small number of 
modes, in which case a Krylov subspace technique would likely be preferred.

Jack

On Tuesday, March 8, 2016 at 8:20:10 PM UTC-8, Jack Poulson wrote:
>
> There were several recent extensions to Elemental's SVD support, as 
> detailed here:
> https://github.com/elemental/Elemental/issues/125
>
> In particular, FULL_SVD, THIN_SVD, COMPACT_SVD, and PRODUCT_SVD are now 
> all supported, where the latter should used if you do not need small 
> triplets as it uses a more parallelizable reduction to tridiagonal form of 
> A^H A rather than a reduction to bidiagonal form of A (as well as a more 
> parallelized MRRR Hermitian tridiagonal eigensolver instead of a QR 
> algorithm for the bidiagonal SVD).
>
> With that said, it's worth asking if your friend only needs the top k 
> triplets for modest k, as something like Jiahao and Andreas's TSVD 
> implementation on top of a distributed dense matrix-vector product likely 
> be the way to go (otherwise, a wrapper to SLEPc would be warranted).
>
> Jack
>
> On Tuesday, March 8, 2016 at 12:19:07 PM UTC-8, Tony Kelman wrote:
>>
>> May also want to look into Elemental. Last I checked Elemental uses 
>> Scalapack in a handful of places but I don't think it would be the case 
>> here.
>>
>>
>> On Tuesday, March 8, 2016 at 8:19:15 AM UTC-8, Erik Schnetter wrote:
>>>
>>> A colleague mentioned to me that he needs to diagonalize (find 
>>> eigenvalues and eigenvectors) of a symmetric dense matrix with n=10^6 
>>> (i.e. the matrix has 10^12 entries). ScaLapack seems to be the way to 
>>> go for this. 
>>>
>>> I'm happy to see there is 
>>> <https://github.com/JuliaParallel/ScaLAPACK.jl>. Saying its 
>>> documentation is "Spartan" is an understatement. There is a file 
>>> "test/test.jl" that seems to not be included from "runtests.jl", and 
>>> which thus might be intended as example. 
>>>
>>> The package doesn't pass its tests. If you know more about whether 
>>> this just needs a brush-up or whether major surgery is required I'd 
>>> appreciate feedback. 
>>>
>>> -erik 
>>>
>>> -- 
>>> Erik Schnetter <[email protected]> 
>>> http://www.perimeterinstitute.ca/personal/eschnetter/ 
>>>
>>

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