Minimize on GPU using L-BFGS algorithm (doesn't support shake constraints)

[mattsperanza]

Implementation requires c++11 features for function calls. L-BFGS options (grms tolerance and gradient history) can be set using the "run setvariable" commands.

[mattsperanza]

While constraints are not supported (and they would be difficult to implement, best bet is an augmented Lagrangian method), proper use of the checkpoint file system lets you turn off shake, minimize, turn on shake, and run energy/dynamics. This is useful property of deleting the "system" and restarting with every run command. The energy changes when the constraints are added (bonds/vdw removed).

As an example:
"
...init stuff

run setvariable fnmcpi res/{sysname}_prod{itt}.res
run setvariable fnmcpo res/{sysname}_prod{itt}.res

... more details

structure shake none
run setvariable nsteps 200
run setvariable mintype lbfgs
run minimize ! writes a checkpoint file, deletes system when minimize steps finish

structure shake hbond
run energy ! reads checkpoint file just write, builds new system with constraints
"