This is part of the colvar module

Return one or more constant quantities with or without derivatives.

Useful in combination with functions that takes in input constants or parameters.

Description of components

The names of the components in this action can be customized by the user in the actions input file. However, in addition to these customizable components the following quantities will always be output

Quantity	Description
v	the # value

Compulsory keywords

VALUES	( default=NAN ) The values of the constants
VALUE	( default=NAN ) The value of the constant

Options

NOPBC

( default=off ) ignore the periodic boundary conditions when calculating distances

NODERIV

( default=off ) Set to TRUE if you want values without derivatives.

Examples

The following input instructs plumed to compute the distance between atoms 1 and 2. If this distance is between 1.0 and 2.0, it is printed. If it is lower than 1.0 (larger than 2.0), 1.0 (2.0) is printed

cn: CONSTANT VALUES=1.0,2.0
dis: DISTANCE ATOMS=1,2
sss: SORT ARG=cn.v_0,dis,cn.v_1
PRINT ARG=sss.2

(See also DISTANCE, SORT, and PRINT).

In case you want to pass a single value you can use VALUE:

cn: CONSTANT VALUE=1.0
dis: DISTANCE ATOMS=1
sss: SORT ARG=cn,dis
PRINT ARG=sss.1