GEOMETRIC_PATH
This is part of the mapping module
It is only available if you configure PLUMED with ./configure –enable-modules=mapping . Furthermore, this feature is still being developed so take care when using it and report any problems on the mailing list.

Distance along and from a path calculated using geometric formulas

Examples
Glossary of keywords and components
Description of components

By default this Action calculates the following quantities. These quantities can be referenced elsewhere in the input by using this Action's label followed by a dot and the name of the quantity required from the list below.

Quantity Description
s the position on the path
z the distance from the path
Compulsory keywords
METRIC the method to use for computing the displacement vectors between the reference frames
METRIC_COMPONENT if the final action in your metric contains multiple components this keyword is used to specify the component that should be used
REFERENCE labels for actions that contain reference coordinates for each point on the path
PROPERTY the coordinates we are projecting these points onto
Options
SERIAL

( default=off ) do the calculation in serial. Do not parallelize

ARG the input for this action is the scalar output from one or more other actions. The particular scalars that you will use are referenced using the label of the action. If the label appears on its own then it is assumed that the Action calculates a single scalar value. The value of this scalar is thus used as the input to this new action. If * or *.* appears the scalars calculated by all the proceeding actions in the input file are taken. Some actions have multi-component outputs and each component of the output has a specific label. For example a DISTANCE action labelled dist may have three components x, y and z. To take just the x component you should use dist.x, if you wish to take all three components then use dist.*.More information on the referencing of Actions can be found in the section of the manual on the PLUMED Getting Started. Scalar values can also be referenced using POSIX regular expressions as detailed in the section on Regular Expressions. To use this feature you you must compile PLUMED with the appropriate flag.. You can use multiple instances of this keyword i.e. ARG1, ARG2, ARG3...