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NTHL

By default, the pseudo-arclength stepsize includes all state variables (or state functions) and all free parameters. Under certain circumstances one may want to modify the weight accorded to individual parameters in the definition of stepsize. For this purpose, NTHL defines the number of parameters whose weight is to be modified. If NTHL=0 then all weights will have default value 1.0 . If NTHL$ >$0 then one must enter NTHL pairs,  Parameter Index  Weight , with each pair on a separate line.

For example, for the computation of periodic solutions it is recommended that the period not be included in the pseudo-arclength continuation stepsize, in order to avoid period-induced limitations on the stepsize near orbits of infinite period. This exclusion can be accomplished by setting NTHL=1, with, on a separate line, the pair  11  0.0 . Most demos that compute periodic solutions use this option; see for example demo ab.



Gabriel Lord 2007-11-19