Action: DRR
| Module | drr |
|---|---|
| Description | Usage |
| Used to performed extended-system adaptive biasing force(eABF) |   |
Output components
This action calculates the values in the following table. These values can be referenced elsewhere in the input by using this Action’s label followed by a dot and the name of the value required from the list below.
| Name | Type | Description |
|---|---|---|
| bias | scalar | the instantaneous value of the bias potential |
| _fict | scalar | one or multiple instances of this quantity can be referenced elsewhere in the input file |
| _vfict | scalar | one or multiple instances of this quantity can be referenced elsewhere in the input file |
| _biasforce | scalar | The bias force from eABF/DRR of the fictitious particle |
| _springforce | scalar | Spring force between real CVs and extended CVs |
| _fictNoPBC | scalar | the positions of fictitious particles (without PBC) |
Input
The arguments that serve as the input for this action are specified using one or more of the keywords in the following table.
| Keyword | Type | Description |
|---|---|---|
| ARG | scalar | the labels of the scalars on which the bias will act |
Further details and examples
Text from manual goes here
Syntax
The following table describes the keywords and options that can be used with this action
| Keyword | Type | Default | Description |
|---|---|---|---|
| ARG | input | none | the labels of the scalars on which the bias will act |
| TAU | compulsory | 0.5 | specifies relaxation time on each of variables are, similar to extended Time Constant in Colvars |
| FRICTION | compulsory | 8.0 | add a friction to the variable, similar to extended Langevin Damping in Colvars |
| GRID_MIN | compulsory | none | the lower bounds for the grid (GRID_BIN or GRID_SPACING should be specified) |
| GRID_MAX | compulsory | none | the upper bounds for the grid (GRID_BIN or GRID_SPACING should be specified) |
| REFLECTINGWALL | compulsory | 0 | whether add reflecting walls for each CV at GRID_MIN and GRID_MAX |
| FULLSAMPLES | compulsory | 500 | number of samples in a bin prior to application of the ABF |
| MAXFACTOR | compulsory | 1.0 | maximum scaling factor of biasing force |
| OUTPUTFREQ | compulsory | none | write results to a file every N steps |
| NUMERICAL_DERIVATIVES | optional | false | calculate the derivatives for these quantities numerically |
| KAPPA | optional | not used | specifies that the restraint is harmonic and what the values of the force constants on each of the variables are (default to k_BT/(GRID_SPACING)^2) |
| GRID_BIN | optional | not used | the number of bins for the grid |
| GRID_SPACING | optional | not used | the approximate grid spacing (to be used as an alternative or together with GRID_BIN) |
| ZGRID_MIN | optional | not used | the lower bounds for the grid (ZGRID_BIN or ZGRID_SPACING should be specified) |
| ZGRID_MAX | optional | not used | the upper bounds for the grid (ZGRID_BIN or ZGRID_SPACING should be specified) |
| ZGRID_BIN | optional | not used | the number of bins for the grid |
| ZGRID_SPACING | optional | not used | the approximate grid spacing (to be used as an alternative or together with ZGRID_BIN) |
| EXTERNAL_FORCE | optional | not used | use forces from other action instead of internal spring force, this disable the extended system! |
| EXTERNAL_FICT | optional | not used | position of external fictitious particles, useful for UIESTIMATOR |
| HISTORYFREQ | optional | not used | save history to a file every N steps |
| NOCZAR | optional | false | disable the CZAR estimator |
| UI | optional | false | enable the umbrella integration estimator |
| UIRESTARTPREFIX | optional | not used | specify the restart files for umbrella integration |
| OUTPUTPREFIX | optional | not used | specify the output prefix (default to the label name) |
| TEMP | optional | not used | the system temperature - needed when FRICTION is present |
| EXTTEMP | optional | not used | the temperature of extended variables (default to system temperature) |
| DRR_RFILE | optional | not used | specifies the restart file ( |
| NOBIAS | optional | false | DO NOT apply bias forces |
| TEXTOUTPUT | optional | false | use text output for grad and count files instead of boost::serialization binary output |
| MERGEHISTORYFILES | optional | false | output all historic results to a single file rather than multiple |
| FMT | optional | not used | specify format for outfiles files (useful for decrease the number of digits in regtests) |