[petsc-users] About SLEPC's EPSSetDeflationSpace implementation

[Jose E. Roman]

It is deflation by orthogonalization. The vectors provided with EPSSetDeflationSpace() are converted to an orthonormal basis (orthogonalizing column by column) and then all vectors generated by the solver are orthogonalized against this basis. In this way, the solver operates in the orthogonal complement of the deflation space.

Jose


> El 18 sept 2018, a las 9:44, Reinaldo Astudilo - EWI <R.A.Astudillo at tudelft.nl> escribió:
> 
> Dear Petsc/Slepc users,
> 
> I'd like to know what algorithm SLEPC implements for deflation set by EPSSetDeflationSpace.
> 
> Could anyone knows this or point out any reference?
> 
> Thank you in advance
> 
> Reinaldo
>