SNESQNScaleType#
the scaling type used by SNESQN
Values#
- SNES_QN_SCALE_NONE- don’t scale the problem
- SNES_QN_SCALE_SCALAR- use Shanno scaling
- SNES_QN_SCALE_DIAGONAL- scale with a diagonalized BFGS formula (see Gilbert and Lemarechal 1989), available
- SNES_QN_SCALE_JACOBIAN- scale by solving a linear system coming from the Jacobian you provided with- SNESSetJacobian()computed at the first iteration of- SNESQNand at ever restart.
Options Database Key#
- -snes_qn_scale_type <diagonal,none,scalar,jacobian> - Scaling type 
See Also#
SNES, SNESQN, SNESQNSetScaleType(), SNESQNType, SNESQNSetType(), SNESQNSetRestartType(), SNESQNRestartType`
Level#
intermediate
Location#
Index of all SNES routines
Table of Contents for all manual pages
Index of all manual pages