IADS

This constant controls the frequency of adaption of the pseudo-arclength stepsize.

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IADS=0 : Use fixed pseudo-arclength stepsize, i.e., the stepsize will be equal to the specified value of DS for every step. The computation of a family will be discontinued as soon as the maximum number of iterations ITNW is reached. This choice is not recommended.
(Demo tim.)

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IADS$>$0 : Adapt the pseudo-arclength stepsize after every IADS steps. If the Newton/Chord iteration converges rapidly then $\mid\tt DS\mid$ will be increased, but never beyond DSMAX. If a step fails then it will be retried with half the stepsize. This will be done repeatedly until the step is successful or until $\mid\tt DS\mid$ reaches DSMIN. In the latter case nonconvergence will be signalled. The strongly recommended value is IADS=1, which is used in almost all demos.