NAME
     CalcMatch - calculate best matching structure parts

SYNOPSIS
     CalcMatch expr expr

DESCRIPTION
     Determines which parts of all selected molecules can
     be superimposed with the smallest RMSD, taking into
     account all selected atoms of all selected residues.
     The structures do not need to be identical, but the
     same number of residues with the same number of atoms
     each must be selected. The structures do not need to
     be superimposed before executing the command.

     The first argument gives the minimal number of
     residues that must be superimposed, the second
     argument the maximal RMSD (to the mean) desired.

     The algorithm is relatively simple, it superimposes
     the structures with the current set of atoms (starting
     with all selected ones), and in each step it leaves
     away the atoms from the residue that has the largest
     global displacement. This is repeated until one of
     the conditions given by the arguments is met.

     A protocol of the progress, giving RMSD and largest
     displacement, is printed. All values are to the mean.
     At the end, an expression for selecting the
     superimposed residues for each molecule is printed.
     The property "match" is set on all these residues.

     This command supports groups.

EXAMPLE
     CalcMatch 50 0.7

SEE ALSO
     SelectMol, SelectAtom, Group, Fit, CalcRmsd

DATE
     960323
