WHAM_WEIGHTS
 This is part of the analysis module

Calculate and output weights for configurations using the weighted histogram analysis method.

This shortcut action allows you to calculate and output weights computed using the weighted histogram analysis technique. For more detail on how this technique works see REWEIGHT_WHAM

Examples

The following input can be used to analyze the output from a series of umbrella sampling calculations. The trajectory from each of the simulations run with the different biases should be concatenated into a single trajectory before running the following analysis script on the concatenated trajectory using PLUMED driver. The umbrella sampling simulations that will be analyzed using the script below applied a harmonic restraint that restrained the torsional angle involving atoms 5, 7, 9 and 15 to particular values. The script below calculates the reweighting weights for each of the trajectories and then applies the binless WHAM algorithm to determine a weight for each configuration in the concatenated trajectory.

Click on the labels of the actions for more information on what each action computes

The script above must be run with multiple replicas using the following command:

mpirun -np 4 plumed driver --mf_xtc alltraj.xtc --multi 4

Glossary of keywords and components
Compulsory keywords
 BIAS ( default=*.bias ) the value of the biases to use when performing WHAM TEMP the temperature at which the simulation was run STRIDE ( default=1 ) the frequency with which the bias should be stored to perform WHAM FILE the file on which to output the WHAM weights
Options
 FMT the format to use for the real numbers in the output file