[gmx-users] how to neutralise: Non-integer charges

[Erik Marklund]

namita at ncbs.res.in skrev:
> Dear users
>
> If you get a non-integer value for a charge, then how can you add charegs
> to your system?
>
> Eg:
>
> NOTE:
> System has non-zero total charge: -9.999998e+00
>
>
> This error is possibly due to the topology file but then how can it be
> recorrected?
>
> Thanks
> SIncerely
> Namitha
>
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Hi,


Your charge is VERY clse to -10. I'd ignore it. It's probably due to 
summation of many floating point numbers, or the inability of floats to 
represent all decimal numbers.

/Erik

-- 
-----------------------------------------------
Erik Marklund, PhD student
Laboratory of Molecular Biophysics,
Dept. of Cell and Molecular Biology, Uppsala University.
Husargatan 3, Box 596,    75124 Uppsala, Sweden
phone:    +46 18 471 4537        fax: +46 18 511 755
erikm at xray.bmc.uu.se    http://xray.bmc.uu.se/molbiophys