[CP2K:127] Re: computational scaling in QS

Fawzi Mohamed fa... at gmx.ch
Thu Jun 7 12:54:29 CEST 2007


... minor corrections to myself ;)

>> 2. OT
>> - On p. 117, the text states that in the most optimal situation the
>> method
>> scales as M*N^2 and M^2*N in the worst case (non-sparse) scenario.
>> - The memory scales as O(M*N) which I is also similar to a PW method
>> but with a localized basis M is substantiall smaller. I imagine the
>> other terms
>> that contribute to the memory scaling, e.g. potential, charge
>> density, etc.
>> are negligible ??

worst case (non sparse) also in OT the memory scales like O(M*M),  
also OT has sparse matrixes

[...]
> On large systems the cubic term of the matrixes dominates, and

ehm, quadratic, for the memory it is quadratic...

> whereas you can still perform calculations using OT it is not
> possible with TD.




More information about the CP2K-user mailing list