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====== GSAS-style Dampening Factors ======
Dampening factor for any refined value (lattice parameters, atomic positions etc.), for those who like to think that they know better than the least squares algorithm.

<code topas>
''Rather than the true GSAS dampening [applied shift = (10-damp)/10], an exponential function is used, scaled to useful dampening values of 0-9
''Useful dampening factors range from values of 0 (no dampening) to 9 (1% applied shift)
''List of DampFactor,AppliedChanges: 0,1; 1,0.607; 2,0.368; 3,0.223; 4,0.135; 5,0.082; 6,0.50; 7,0.030; 8,0.018; 9,0.011
''e.g. A simple lattice parameter refinement with dampening factors of 9, 8, 7, 6, 5, 4, 3, 2, 1 and 0
''     converges in 422, 271, 173, 111, 71, 45, 28, 17, 10 and 5 cycles, respectively
''Example of use: 
'' site O1	x @  0.30696 Damp(3)	y 0	z 0.25	occ O-2	1	beq @ 2 Damp(7)

macro Damp(DampFactor) 
{
   update = Val + (Change*(1/Exp(DampFactor/2))); 
}
</code>