g_sgangle_d (1) - Linux Man Pages
g_sgangle_d: computes the angle and distance between two groups
NAMEg_sgangle - computes the angle and distance between two groups
SYNOPSISg_sgangle -f traj.xtc -n index.ndx -s topol.tpr -oa sg_angle.xvg -od sg_dist.xvg -od1 sg_dist1.xvg -od2 sg_dist2.xvg -[no]h -nice int -b time -e time -dt time -[no]w -[no]xvgr -[no]one -[no]z
DESCRIPTIONCompute the angle and distance between two groups. The groups are defined by a number of atoms given in an index file and may be two or three atoms in size. If -one is set, only one group should be specified in the index file and the angle between this group at time 0 and t will be computed. The angles calculated depend on the order in which the atoms are given. Giving for instance 5 6 will rotate the vector 5-6 with 180 degrees compared to giving 6 5.
If three atoms are given, the normal on the plane spanned by those three atoms will be calculated, using the formula P1P2 x P1P3. The cos of the angle is calculated, using the inproduct of the two normalized vectors.
Here is what some of the file options do:
-oa: Angle between the two groups specified in the index file. If a group contains three atoms the normal to the plane defined by those three atoms will be used. If a group contains two atoms, the vector defined by those two atoms will be used.
-od: Distance between two groups. Distance is taken from the center of one group to the center of the other group.
-od1: If one plane and one vector is given, the distances for each of the atoms from the center of the plane is given seperately.
-od2: For two planes this option has no meaning.
FILES-f traj.xtc Input
-nice int 19
-b time 0
-e time 0
-dt time 0
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