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

The following command will extract .grad and .count files.

plumed drr_tool --extract eabf.drrstate

The following command will merge windows of two .drrstate file, and output the .grad and .count files.

plumed drr_tool --merge win1.drrstate,win2.drrstate

After getting the .grad and .count file, you can do numerical integration by using abf_integrate tool from https://github.com/Colvars/colvars/tree/master/colvartools

abf_integrate eabf.czar.grad

Note: The abf_integrate in colvartools is in kcal/mol, so it may be better to use –units kcal/mol when running drr_tool

--units ( default=kj/mol ) the units of energy can be kj/mol, kcal/mol, j/mol, eV or the conversion factor from kj/mol

`--help/-h`	( default=off ) print this help
-v	( default=off ) Verbose output
`--extract`	Extract drrstate file(s)
`--merge`	Merge eABF windows
`--merge_output`	The output filename of the merged result
`--divergence`	Calculate divergence of gradient field (experimental)
`--dump-fmt`	( default=%f ) the format to use to dump the output