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11 <td ALIGN=LEFT VALIGN=TOP WIDTH=
280><br><h2>g_enemat
</h2><font size=-
1><A HREF=
"../online.html">Main Table of Contents
</A></font><br><br></td>
12 </TABLE></TD><TD WIDTH=
"*" ALIGN=RIGHT VALIGN=BOTTOM
><p><B>VERSION
4.5<br>
13 Thu
26 Aug
2010</B></td></tr></TABLE>
17 g_enemat extracts an energy matrix from the energy file (
<tt>-f
</tt>).
18 With
<tt>-groups
</tt> a file must be supplied with on each
19 line a group of atoms to be used. For these groups matrix of
20 interaction energies will be extracted from the energy file
21 by looking for energy groups with names corresponding to pairs
22 of groups of atoms. E.g. if your
<tt>-groups
</tt> file contains:
<br>
26 then energy groups with names like 'Coul-SR:Protein-SOL' and
27 'LJ:Protein-SOL' are expected in the energy file (although
28 <tt>g_enemat
</tt> is most useful if many groups are analyzed
29 simultaneously). Matrices for different energy types are written
30 out separately, as controlled by the
31 <tt>-[no]coul
</tt>,
<tt>-[no]coulr
</tt>,
<tt>-[no]coul14
</tt>,
32 <tt>-[no]lj
</tt>,
<tt>-[no]lj14
</tt>,
33 <tt>-[no]bham
</tt> and
<tt>-[no]free
</tt> options.
34 Finally, the total interaction energy energy per group can be
35 calculated (
<tt>-etot
</tt>).
<p>
36 An approximation of the free energy can be calculated using:
37 E(free) = E0 + kT
<a href=
"log.html">log
</a>(
<exp((E-E0)/kT)
> ), where '
<>'
38 stands for time-average. A file with reference free energies
39 can be supplied to calculate the free energy difference
40 with some reference state. Group names (e.g. residue names)
41 in the reference file should correspond to the group names
42 as used in the
<tt>-groups
</tt> file, but a appended number
43 (e.g. residue number) in the
<tt>-groups
</tt> will be ignored
47 <TABLE BORDER=
1 CELLSPACING=
0 CELLPADDING=
2>
48 <TR><TH>option
</TH><TH>filename
</TH><TH>type
</TH><TH>description
</TH></TR>
49 <TR><TD ALIGN=RIGHT
> <b><tt>-f
</tt></b> </TD><TD ALIGN=RIGHT
> <tt><a href=
"edr.html"> ener.edr
</a></tt> </TD><TD> Input, Opt.
</TD><TD> Energy file
</TD></TR>
50 <TR><TD ALIGN=RIGHT
> <b><tt>-groups
</tt></b> </TD><TD ALIGN=RIGHT
> <tt><a href=
"dat.html"> groups.dat
</a></tt> </TD><TD> Input
</TD><TD> Generic data file
</TD></TR>
51 <TR><TD ALIGN=RIGHT
> <b><tt>-eref
</tt></b> </TD><TD ALIGN=RIGHT
> <tt><a href=
"dat.html"> eref.dat
</a></tt> </TD><TD> Input, Opt.
</TD><TD> Generic data file
</TD></TR>
52 <TR><TD ALIGN=RIGHT
> <b><tt>-emat
</tt></b> </TD><TD ALIGN=RIGHT
> <tt><a href=
"xpm.html"> emat.xpm
</a></tt> </TD><TD> Output
</TD><TD> X PixMap compatible matrix file
</TD></TR>
53 <TR><TD ALIGN=RIGHT
> <b><tt>-etot
</tt></b> </TD><TD ALIGN=RIGHT
> <tt><a href=
"xvg.html"> energy.xvg
</a></tt> </TD><TD> Output
</TD><TD> xvgr/xmgr file
</TD></TR>
56 <H3>Other options
</H3>
57 <TABLE BORDER=
1 CELLSPACING=
0 CELLPADDING=
2>
58 <TR><TH>option
</TH><TH>type
</TH><TH>default
</TH><TH>description
</TH></TR>
59 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]h
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> Print help info and quit
</TD></TD>
60 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]version
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> Print version info and quit
</TD></TD>
61 <TR><TD ALIGN=RIGHT
> <b><tt>-nice
</tt></b> </TD><TD ALIGN=RIGHT
> int
</TD><TD ALIGN=RIGHT
> <tt>19</tt> </TD><TD> Set the nicelevel
</TD></TD>
62 <TR><TD ALIGN=RIGHT
> <b><tt>-b
</tt></b> </TD><TD ALIGN=RIGHT
> time
</TD><TD ALIGN=RIGHT
> <tt>0 </tt> </TD><TD> First frame (ps) to read from trajectory
</TD></TD>
63 <TR><TD ALIGN=RIGHT
> <b><tt>-e
</tt></b> </TD><TD ALIGN=RIGHT
> time
</TD><TD ALIGN=RIGHT
> <tt>0 </tt> </TD><TD> Last frame (ps) to read from trajectory
</TD></TD>
64 <TR><TD ALIGN=RIGHT
> <b><tt>-dt
</tt></b> </TD><TD ALIGN=RIGHT
> time
</TD><TD ALIGN=RIGHT
> <tt>0 </tt> </TD><TD> Only use frame when t MOD dt = first time (ps)
</TD></TD>
65 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]w
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> View output
<a href=
"xvg.html">xvg
</a>,
<a href=
"xpm.html">xpm
</a>,
<a href=
"eps.html">eps
</a> and
<a href=
"pdb.html">pdb
</a> files
</TD></TD>
66 <TR><TD ALIGN=RIGHT
> <b><tt>-xvg
</tt></b> </TD><TD ALIGN=RIGHT
> enum
</TD><TD ALIGN=RIGHT
> <tt>xmgrace
</tt> </TD><TD> <a href=
"xvg.html">xvg
</a> plot formatting:
<tt>xmgrace
</tt>,
<tt>xmgr
</tt> or
<tt>none
</tt> </TD></TD>
67 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]sum
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> Sum the energy terms selected rather than display them all
</TD></TD>
68 <TR><TD ALIGN=RIGHT
> <b><tt>-skip
</tt></b> </TD><TD ALIGN=RIGHT
> int
</TD><TD ALIGN=RIGHT
> <tt>0</tt> </TD><TD> Skip number of frames between data points
</TD></TD>
69 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]mean
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>yes
</tt> </TD><TD> with -groups extracts matrix of mean energies instead of matrix for each timestep
</TD></TD>
70 <TR><TD ALIGN=RIGHT
> <b><tt>-nlevels
</tt></b> </TD><TD ALIGN=RIGHT
> int
</TD><TD ALIGN=RIGHT
> <tt>20</tt> </TD><TD> number of levels for matrix colors
</TD></TD>
71 <TR><TD ALIGN=RIGHT
> <b><tt>-max
</tt></b> </TD><TD ALIGN=RIGHT
> real
</TD><TD ALIGN=RIGHT
> <tt>1e+20 </tt> </TD><TD> max value for energies
</TD></TD>
72 <TR><TD ALIGN=RIGHT
> <b><tt>-min
</tt></b> </TD><TD ALIGN=RIGHT
> real
</TD><TD ALIGN=RIGHT
> <tt>-
1e+20</tt> </TD><TD> min value for energies
</TD></TD>
73 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]coul
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>yes
</tt> </TD><TD> extract Coulomb SR energies
</TD></TD>
74 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]coulr
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> extract Coulomb LR energies
</TD></TD>
75 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]coul14
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> extract Coulomb
1-
4 energies
</TD></TD>
76 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]lj
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>yes
</tt> </TD><TD> extract Lennard-Jones SR energies
</TD></TD>
77 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]lj
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> extract Lennard-Jones LR energies
</TD></TD>
78 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]lj14
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> extract Lennard-Jones
1-
4 energies
</TD></TD>
79 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]bhamsr
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> extract Buckingham SR energies
</TD></TD>
80 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]bhamlr
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>no
</tt> </TD><TD> extract Buckingham LR energies
</TD></TD>
81 <TR><TD ALIGN=RIGHT
> <b><tt>-[no]free
</tt></b> </TD><TD ALIGN=RIGHT
> gmx_bool
</TD><TD ALIGN=RIGHT
> <tt>yes
</tt> </TD><TD> calculate free energy
</TD></TD>
82 <TR><TD ALIGN=RIGHT
> <b><tt>-temp
</tt></b> </TD><TD ALIGN=RIGHT
> real
</TD><TD ALIGN=RIGHT
> <tt>300 </tt> </TD><TD> reference temperature for free energy calculation
</TD></TD>
87 <font size=
"-1"><a href=
"http://www.gromacs.org">http://www.gromacs.org
</a></font><br>
88 <font size=
"-1"><a href=
"mailto:gromacs@gromacs.org">gromacs@gromacs.org
</a></font><br>