IBM Release 1.93 manual Limit, Store, Penalty Merit

	supplied, guess N+2 overwrites guess 1, and so on. You can supply
	a pre-computed value for the penalty or merit function, by
	including
	merit=<expression> or
	penalty=<expression>
	in the GUESS statement. While this can save valuable time, it must
	be used with care, because POEMS will trust the value you give it. If
	the value is stale or otherwise incorrect, this will interfere with the
	optimization. If the supplied value is unrealistically poor, the
	optimizer will incorrectly tend to move away from it, good, whereas
	if it is too good, the optimizer may get stuck in that vicinity, trying
	to improve a value that is better than any available computed value.
	Syntax: GUESS <var1> = <expression> <var2> =, <expression>....
	[penalty = <expression>]
LIMIT	Expression that has to be true for a valid point. Often it’s better to
	change the simulation parameters to build the limits in--e.g.
	replacing width with abs(width) or using more complicated
	functions of absolute values. LIMIT is better for more complicated
	functions, e.g. forcing the corners of some structure to lie within an
	arbitrary boundary. Not implemented in this release.
	Syntax: LIMIT <Boolean expression>
	Example: LIMIT length*width*height ≤ MaxVolume
STORE	Specify a file to store the simplex for each iteration, along with the
	corresponding penalty function values. These are in the right
	format to be cut and pasted back into the parameters file to restart
	an interation without losing previous work.
	Syntax: STORE <filename>
PENALTY
MERIT	Defines an expression on which the optimizer is to work. Merit
	functions are maximized, and penalty functions are minimized.
	Only one of the two can be specified. In order for the optimizer to
	do anything useful, the optimization expression must depend on
	each of the optimization variables. Note that any variable
	assignment involving quantities computed by the postprocessor will
	not be updated at postprocessing time. That means that the
	dependence on this iteration’s results must be included explicitly in
	<expression>. For example, if the iteration is minimizing the loss of
	a coupler, you might specify MERIT 10*log10(efficiency), which
	will work fine, but you can’t use SET dBloss=-
	10*log10(efficiency) up in the GLOBAL section and then specify
	PENALTY dBloss in the OPTIMIZE section--if you do, you’ll wind
	up with stale data. This can sometimes be useful, but not usually.

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