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fire_bfgs_minimization [2011/08/12 11:44]
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fire_bfgs_minimization [2011/08/12 11:47]
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-====== BFGS ====== 
-it call [[http://​users.eecs.northwestern.edu/​~nocedal/​lbfgsb.html|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 
-   ​nstepf = 1000 ! ! Max number of opt steps, default value = 100 
-   dt = 0.5 !/only if FIRE minimization is used - last parameter in cgopt.optional >0/ 
- 
-==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 USED in BFGS 
-   ​0.1 ​                 ! dummy argument - NOT USED in BFGS 
-   ​0.00000001 ​          ! total energy tolerance ​ - NOT USED in BFGS 
-   ​0.001 ​               ! fmax - force tolerance - end of minimization if fij<fmax 
-   ​10000 ​               ! Max number of opt steps - NOT USED IN BFGS - now the max. number of steps is given by parameter nstepf in firaball.in 
-   ​0 ​                   !number of restarts in case ftot>​fmax (it seems it nave 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 
-   ​nstepf = 100 ! Max number of opt steps 
-   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 USED 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 ​           ! NOT MORE USED IN FIRE, Max number of opt steps - NOT MORE USED IN FIRE - see parametr nstepf in fireball.in 
-   ​0 ​               ! NOT USED in FIRE minimization 
- 
  
fire_bfgs_minimization.txt ยท Last modified: 2011/08/12 11:47 (external edit)