ALPRAXIN is a program to position a structure
such that its principal inertia vectors are aligned
with the coordinate axes.
The structure can be a low-resolution bead model and/or
a high resolution NMR or x-ray crystal structure.
The principal axes of inertia are calculated for a given set
of atoms as eigenvectors of the inertia tensor. The structure is
centered at the origin and rotated to have the principal axes aligned with the
coordinate axes. The aligned structure is saved in the output file.
Please refer to the paper cited above for further details about the implemented algorithm.
Following a successful superposition, ALPRAXIN creates a single output
file for the aligned structure. By default the output filename is taken
from the input target structure but is appended with 'r', eg.
$ alpraxin file1.pdb
yields file1r.pdb as output. A different filename can be specified
with the --output option.