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 | VERSION 3.3.1 | 
g_rmsf computes the root mean square fluctuation (RMSF, i.e. standard deviation) of atomic positions after (optionally) fitting to a reference frame.
With option -oq the RMSF values are converted to B-factor values, which are written to a pdb file with the coordinates, of the structure file, or of a pdb file when -q is specified. Option -ox writes the B-factors to a file with the average coordinates.
With the option -od the root mean square deviation with respect to the reference structure is calculated.
With the option aniso g_rmsf will compute anisotropic temperature factors and then it will also output average coordinates and a pdb file with ANISOU records (corresonding to the -oq or -ox option). Please note that the U values are orientation dependent, so before comparison with experimental data you should verify that you fit to the experimental coordinates.
When a pdb input file is passed to the program and the -aniso flag is set a correlation plot of the Uij will be created, if any anisotropic temperature factors are present in the pdb file.
With option -dir the average MSF (3x3) matrix is diagonalized. This shows the directions in which the atoms fluctuate the most and the least.
| option | filename | type | description | 
|---|---|---|---|
| -f | traj.xtc | Input | Generic trajectory: xtc trr trj gro g96 pdb | 
| -s | topol.tpr | Input | Structure+mass(db): tpr tpb tpa gro g96 pdb xml | 
| -n | index.ndx | Input, Opt. | Index file | 
| -q | eiwit.pdb | Input, Opt. | Protein data bank file | 
| -oq | bfac.pdb | Output, Opt. | Protein data bank file | 
| -ox | xaver.pdb | Output, Opt. | Protein data bank file | 
| -o | rmsf.xvg | Output | xvgr/xmgr file | 
| -od | rmsdev.xvg | Output, Opt. | xvgr/xmgr file | 
| -oc | correl.xvg | Output, Opt. | xvgr/xmgr file | 
| -dir | rmsf.log | Output, Opt. | Log file | 
| option | type | default | description | 
|---|---|---|---|
| -[no]h | bool | no | Print help info and quit | 
| -nice | int | 19 | Set the nicelevel | 
| -b | time | 0 | First frame (ps) to read from trajectory | 
| -e | time | 0 | Last frame (ps) to read from trajectory | 
| -dt | time | 0 | Only use frame when t MOD dt = first time (ps) | 
| -[no]w | bool | no | View output xvg, xpm, eps and pdb files | 
| -[no]xvgr | bool | yes | Add specific codes (legends etc.) in the output xvg files for the xmgrace program | 
| -[no]res | bool | no | Calculate averages for each residue | 
| -[no]aniso | bool | no | Compute anisotropic termperature factors | 
| -[no]fit | bool | yes | Do a least squares superposition before computing RMSF. Without this you must make sure that the reference structure and the trajectory match. |