Interpolate a smooth function stored on a grid onto a grid with a smaller grid spacing.

This action takes a function evaluated on a grid as input and can be used to interpolate the values of that function on to a finer grained grid. The interpolation within this algorithm is done using splines.


The input below can be used to post process a trajectory. It calculates a HISTOGRAM as a function the distance between atoms 1 and 2 using kernel density estimation. During the calculation the values of the kernels are evaluated at 100 points on a uniform grid between 0.0 and 3.0. Prior to outputting this function at the end of the simulation this function is interpolated onto a finer grid of 200 points between 0.0 and 3.0.

Click on the labels of the actions for more information on what each action computes
tested on v2.8
the pair of atom that we are calculating the distance between.
the input for this action is the scalar output from one or more other actions.
compulsory keyword the lower bounds for the grid
compulsory keyword the upper bounds for the grid
the number of bins for the grid
compulsory keyword the bandwidths for kernel density estimation
compulsory keyword the action that creates the input grid you would like to use
the number of bins for the grid
compulsory keyword the action that creates the grid you would like to output
compulsory keyword ( default=density ) the file on which to write the grid.
Glossary of keywords and components
Compulsory keywords
STRIDE ( default=1 ) the frequency with which the data should be collected and added to the quantity being averaged
CLEAR ( default=0 ) the frequency with which to clear all the accumulated data. The default value of 0 implies that all the data will be used and that the grid will never be cleared
NORMALIZATION ( default=true ) This controls how the data is normalized it can be set equal to true, false or ndata. The differences between these options are explained in the manual page for HISTOGRAM
GRID the action that creates the input grid you would like to use
SERIAL ( default=off ) do the calculation in serial. Do not use MPI
LOWMEM ( default=off ) lower the memory requirements

( default=off ) output information on the timings of the various parts of the calculation

LOGWEIGHTS list of actions that calculates log weights that should be used to weight configurations when calculating averages
CONCENTRATION the concentration parameter for Von Mises-Fisher distributions
COMPONENT if your input is a vector field use this to specify the component of the input vector field for which you wish to use
GRID_BIN the number of bins for the grid
GRID_SPACING the approximate grid spacing (to be used as an alternative or together with GRID_BIN)