amo pdb2voxel \
-index <STRING> \
-dirt <STRING> \
-output <STRING|optional>
-- Notes:
-- each line in the index file is similar to
-- 6qspA02.pdb,2.9325,32.8724,6.1531
-- where the 1st is the PDB file name, the 2nd to end are the coordinate (x, y, z) of the mass centroid
-- Options:
-- -type <BOOL>: represent an atom by using the Rubik's cube (3x3x3) or not
-- -index <STRING>: index for proteins those are converted to voxel representations
-- -dirt <STRING>: path to the directory where the proteins are stored
-- -backbone <BOOL>: backbone of a protein, now supports N, CA, C, O, CB
-- -atom_type <STRING>: what type of an atom is used for the voxel representation
-- -alpha <DOUBLE>: the edge length of the cube, default is 2048.0
-- -beta <INT>: number of voxels, default is 512
-- -threads <INT>: number of threads, default is 2