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fire_bfgs_minimization

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BFGS

it call l-bfgs-b routine till: - the convergence criteria defined in cg.optional are reached (f(i,j)<fmax for all i,j) - the algorithm is not able to find the smaller energy in spite of f>fmax - the maximum number of steps exceeds

setting of input files:

fireball.in:
 iquench = -5
cgopt.optional:

This routine uses the same input file as Conjiged Gradients (iquench = -4). It does not use all parameters, but they must be there.

 0.1                  ! max displacement - not use in BFGS
 0.1                  ! dummy argument - not use in BFGS
 0.00000001              ! total energy tolerance  - not use in BFGS
 0.001                 ! fmax - force tolerance - end of minimization if fij<fmax
 10000                 ! Max number of opt steps
 0                     !number of restarts after BFGS convergence (not use now - restarts have no effect)
 0                    !if >0 then dt must be defined in fireball.in. Number of FIRE **downhill** steps after BFGS minimization fails

FIRE

setting of input files:

fireball.in:
 iquench = -6
 dt = 0.5 !timestep in MD
cgopt.optional:

This routine uses the same input file as Conjiged Gradients (iquench = -4). It does not use all parameters, but they must be there.

 0.1                  ! max displacement 
 0.5                  ! not use in FIRE
 0.0              ! total energy tolerance  - the walker can make step uphill if Enew-Emin<Etol, Etol=0 => only downhill steps allowed
 0.001                 ! fmax - force tolerance - end of minimization if fij<fmax
 10000                 ! Max number of opt steps
 0                    ! not use in FIRE minimization
fire_bfgs_minimization.1304948904.txt.gz · Last modified: 2011/05/09 15:48 (external edit)