gmx rms rmsf rmsdist
总结
gmx rms -f *.xtc -s *.tpr -o *_rmsd.xvg -m *_rmsd.xpm -tu ns
gmx rmsf -f *.xtc -s *.tpr -oq *_bfactor.pdb(默认写到-s文件中，或者用-q提供一个新的pdb写入bfactor) -o *_rmsf.xvg -res(一定要加，否则算的是atom的)
几个概念：rmsd vs rmsf vs rmsdist
RMSD是对原子总数求平均，RMSF是对单个原子时间求平均
RMSD表示的是分子结构变化的程度，而RMSF值表示的是分子中各个原子运动的自由程度
rmsd
计算的是某个结构（N个原子）相对于参考结构（-s指定）的 root mean square deviation
gmx rms 没法设置τ，只有rmsd.xpm矩阵
rmsf
计算的是一个原子在一段时间的平均，和bfactor有关
rmsdist 计算的是原子i和j直接的距离随时间的变化大小，rmsd算的是原子i相对自己的位置变化大小
OPTIONS
Options to specify input files:
-s [<.tpr/.gro/...>] (topol.tpr) //参考结构reference structure
Structure+mass(db): tpr gro g96 pdb brk ent
The reference structure is taken from the structure file (-s).
-f [<.xtc/.trr/...>] (traj.xtc)
Trajectory: xtc trr cpt gro g96 pdb tng
Each structure from a trajectory (-f) is compared to a reference structure.
-f2 [<.xtc/.trr/...>] (traj.xtc) (Opt.) //算矩阵的时候，默认是第一个trj和第一个trj每一帧计算rmsd，用-f2则是第一个trj和第二个trj每一帧比较rmsd
Trajectory: xtc trr cpt gro g96 pdb tng
With -f2, the 'other structures' are taken from a second trajectory, this generates a comparison matrix of one trajectory versus the other.
-n [<.ndx>] (index.ndx) (Opt.)
Index file
Options to specify output files:
-o [<.xvg>] (rmsd.xvg)
xvgr/xmgr file
-mir [<.xvg>] (rmsdmir.xvg) (Opt.) // the mirror image of the reference structure 不需要
xvgr/xmgr file
With option -mir also a comparison with the mirror image of the reference structure is calculated. This is useful as a reference for 'significant' values, see Maiorov & Crippen, Proteins 22, 273 (1995).
-a [<.xvg>] (avgrp.xvg) (Opt.) 不需要
xvgr/xmgr file
avgrp.xvg
aver.xvg 输出的信息有误，横坐标应是Atom，该图计算的是每个原子相对于ref structure(-s)的fluctuation（rmsf），没有用
-dist [<.xvg>] (rmsd-dist.xvg) (Opt.) 不需要
xvgr/xmgr file
-m [<.xpm>] (rmsd.xpm) (Opt.)
X PixMap compatible matrix file
Option -m produces a matrix in .xpm format of comparison values of each structure in the trajectory with respect to each other structure. This file can be visualized with for instance xv and can be converted to postscript with gmx xpm2ps.
-bin [<.dat>] (rmsd.dat) (Opt.)
Generic data file
Option -bin does a binary dump of the comparison matrix.
-bm [<.xpm>] (bond.xpm) (Opt.) //角度的矩阵
X PixMap compatible matrix file
Option -bm produces a matrix of average bond angle deviations analogously to the -m option. Only bonds between atoms in the comparison group are considered.
Other options:
-b <time> (0)
Time of first frame to read from trajectory (default unit ps)
-e <time> (0)
Time of last frame to read from trajectory (default unit ps)
-dt <time> (0)
Only use frame when t MOD dt = first time (default unit ps)
-tu <enum> (ps)
Unit for time values: fs, ps, ns, us, ms, s
-[no]w (no)
View output .xvg, .xpm, .eps and .pdb files
-xvg <enum> (xmgrace)
xvg plot formatting: xmgrace, xmgr, none
-what <enum> (rmsd)
Structural difference measure: rmsd, rho, rhosc
gmx rms compares two structures by computing the root mean square deviation (RMSD), the size-independent rho similarity parameter (rho) or the scaled rho (rhosc), see Maiorov & Crippen, Proteins 22, 273 (1995). This is selected by -what
-[no]pbc (yes)
PBC check
-fit <enum> (rot+trans) //默认rot+trans，不需要
Fit to reference structure: rot+trans, translation, none
Option -fit controls the least-squares fitting of the structures on top of each other: complete fit (rotation and translation), translation only, or no fitting at all.
-prev <int> (0) //而不是ref
Compare with previous frame
Option -prev produces the comparison with a previous frame the specified number of frames ago.
-[no]split (no)
Split graph where time is zero
-skip <int> (1)
Only write every nr-th frame to matrix
-skip2 <int> (1)
Only write every nr-th frame to matrix
-max <real> (-1)
Maximum level in comparison matrix
-min <real> (-1)
Minimum level in comparison matrix
-bmax <real> (-1)
Maximum level in bond angle matrix
-bmin <real> (-1)
Minimum level in bond angle matrix
-[no]mw (yes) 不需要
Use mass weighting for superposition
Option -mw controls whether mass weighting is done or not. If you select the option (default) and supply a valid .tpr file masses will be taken from there, otherwise the masses will be deduced from the atommass.dat file in GMXLIB. This is fine for proteins, but not necessarily for other molecules. A default mass of 12.011 amu (carbon) is assigned to unknown atoms. You can check whether this happened by turning on the -debug flag and inspecting the log file.
-nlevels <int> (80) //xpm为的z分80个level,不需要改
Number of levels in the matrices
-ng <int> (1) //意思可能是可以算两个grp的rms
Number of groups to compute RMS between
gmx rmsf
OPTIONS
Options to specify input files:
-f [<.xtc/.trr/...>] (traj.xtc)
Trajectory: xtc trr cpt gro g96 pdb tng
-s [<.tpr/.gro/...>] (topol.tpr) // a reference frame
Structure+mass(db): tpr gro g96 pdb brk ent
gmx rmsf computes the root mean square fluctuation (RMSF, i.e. standard deviation) of atomic positions in the trajectory (supplied with -f) after (optionally) fitting to a reference frame (supplied with -s).
-n [<.ndx>] (index.ndx) (Opt.)
Index file
-q [<.pdb>] (eiwit.pdb) (Opt.)
Protein data bank file
Options to specify output files:
-oq [<.pdb>] (bfac.pdb) (Opt.) //计算并保存B-factor values到-s提供的结构中 或者 可以用-q提供一个新的pdb结构
Protein data bank file
With option -oq the RMSF values are converted to B-factor values, which are written to a .pdb file. By default, the coordinates in this output file are taken from the structure file provided with -s,although you can also use coordinates read from a different .pdb file provided with -q. There is very little error checking, so in this caseit is your responsibility to make sure all atoms in the structure file and .pdb file correspond exactly to each other.
-ox [<.pdb>] (xaver.pdb) (Opt.)//计算并保存B-factor values到平均结构中
Protein data bank file
Option -ox writes the B-factors to a file with the average coordinates in the trajectory.
-o [<.xvg>] (rmsf.xvg)
xvgr/xmgr file
不加-res默认输出atom的fluctuation
加了-res, 因为该蛋白有两条链，res编号有重复，所以出现中间的错误，需手动删除。res是将atom相加求平均而得。
-od [<.xvg>] (rmsdev.xvg) (Opt.) //和rmsf算出来的一样，没用
xvgr/xmgr file
With the option -od the root mean square deviation with respect to the reference structure is calculated.
不加-res默认输出atom的fluctuation，相对于-s结构的
-oc [<.xvg>] (correl.xvg) (Opt.)
xvgr/xmgr file
-dir [<.log>] (rmsf.log) (Opt.)
Log 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.
Other options:
-b <time> (0)
Time of first frame to read from trajectory (default unit ps)
-e <time> (0)
Time of last frame to read from trajectory (default unit ps)
-dt <time> (0)
Only use frame when t MOD dt = first time (default unit ps)
-[no]w (no)
View output .xvg, .xpm, .eps and .pdb files
-xvg <enum> (xmgrace)
xvg plot formatting: xmgrace, xmgr, none
-[no]res (no) //一定要
Calculate averages for each residue
-[no]aniso (no) //各向异性温度因子
Compute anisotropic termperature factors
With the option -aniso, gmx 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.
使用-aniso选项，gmx rmsf将计算各向异性温度因子，然后它还将输出平均坐标和带有ANISOU记录的.pdb文件(与-oq或-ox选项相对应)。请注意U值是与方向相关的，因此在与实验数据进行比较之前，您应该验证您是否适合实验坐标。当将.pdb输入文件传递给程序并设置-aniso标志时，如果.pdb文件中存在任何各向异性温度因子，则会创建Uij的相关图。
-[no]fit (yes)
Do a least squares superposition before computing RMSF. Without this you must make sure that the reference structure and the trajectory match.
gmx rmsdist
computes the root mean square deviation of atom distances, which has the advantage that no fit is needed like in standard RMS deviation as computed by gmx rms. The reference structure is taken from the structure file.
The RMSD at time t is calculated as the RMS of the differences in distance between atom-pairs in the reference structure and the structure at time t.
gmx rmsdist can also produce matrices of the rms distances, rms distances scaled with the mean distance and the mean distances and matrices with NMR averaged distances (1/r^3 and 1/r^6 averaging). Finally, lists of atom pairs with 1/r^3 and 1/r^6 averaged distance below the maximum distance (-max, which will default to 0.6 in this case) can be generated, by default averaging over equivalent hydrogens (all triplets of hydrogens named *[123]).
OPTIONS
Options to specify input files:
-f [<.xtc/.trr/...>] (traj.xtc)
Trajectory: xtc trr cpt gro g96 pdb tng
-s [<.tpr/.gro/...>] (topol.tpr)
Structure+mass(db): tpr gro g96 pdb brk ent
-n [<.ndx>] (index.ndx) (Opt.)
Index file
-equiv [<.dat>] (equiv.dat) (Opt.)
Generic data file
Additionally a list of equivalent atoms can be supplied (-equiv), each line containing a set of equivalent atoms specified as residue number and name and atom name;
e.g.: HB* 3 SER HB1 3 SER HB2. //可能第一列要给距离命名
Residue and atom names must exactly match those in the structure file, including case. Specifying non-sequential atoms is undefined.
此外，还可以提供等效原子列表(-equiv)，每行包含一组等效原子，这些原子指定为残基编号和名称以及原子名称;例如:HB* 3 SER HB1 3 SER HB2。残基编号和原子名称必须与结构文件中的名称完全匹配，包括case。未定义指定非顺序原子。
Options to specify output files:
-o [<.xvg>] (distrmsd.xvg)
xvgr/xmgr file
-rms [<.xpm>] (rmsdist.xpm) (Opt.)
X PixMap compatible matrix file
-scl [<.xpm>] (rmsscale.xpm) (Opt.)
X PixMap compatible matrix file
-mean [<.xpm>] (rmsmean.xpm) (Opt.)
X PixMap compatible matrix file
-nmr3 [<.xpm>] (nmr3.xpm) (Opt.)
X PixMap compatible matrix file
-nmr6 [<.xpm>] (nmr6.xpm) (Opt.)
X PixMap compatible matrix file
-noe [<.dat>] (noe.dat) (Opt.)
Generic data file
Other options:
-b <time> (0)
Time of first frame to read from trajectory (default unit ps)
-e <time> (0)
Time of last frame to read from trajectory (default unit ps)
-dt <time> (0)
Only use frame when t MOD dt = first time (default unit ps)
-[no]w (no)
View output .xvg, .xpm, .eps and .pdb files
-xvg <enum> (xmgrace)
xvg plot formatting: xmgrace, xmgr, none
-nlevels <int> (40)
Discretize RMS in this number of levels
-max <real> (-1)
Maximum level in matrices
-[no]sumh (yes)
Average distance over equivalent hydrogens
-[no]pbc (yes)
Use periodic boundary conditions when computing distances
