| Line 372... |
Line 372... |
|
|
Use PETSC_DECIDE for ncv and mpd to assign a reasonably good value, which is
|
Use PETSC_DECIDE for ncv and mpd to assign a reasonably good value, which is
|
dependent on the solution method.
|
dependent on the solution method.
|
|
|
The parameters ncv and mpd are intimately related, so that the user is advised
|
The parameters ncv and mpd are intimately related, so that the user is advised
|
to set one of them at most. Normal usage is the following:
|
to set one of them at most. Normal usage is that
|
(a) In cases where nev is small, the user sets ncv (a reasonable default is 2*nev).
|
(a) in cases where nev is small, the user sets ncv (a reasonable default is 2*nev); and
|
(b) In cases where nev is large, the user sets mpd.
|
(b) in cases where nev is large, the user sets mpd.
|
|
|
The value of ncv should always be between nev and (nev+mpd), typically
|
The value of ncv should always be between nev and (nev+mpd), typically
|
ncv=nev+mpd. If nev is not too large, mpd=nev is a reasonable choice, otherwise
|
ncv=nev+mpd. If nev is not too large, mpd=nev is a reasonable choice, otherwise
|
a smaller value should be used.
|
a smaller value should be used.
|
|
|