LC-C: How to continue in PD with double period?

[Emil Knut]

Hi to all!

Doing some LC-C, I don't succeed continuing from PD. I'd be very thankful for each kind of advice.

I want to examine some periodic doubling phenomena. Forward and backward continuation is working, it gives me a line in bif.diagram, where stability is lost in a periodic doubling point, comparable to the example PyCont_Lorenz:

Now I want to continue in PD1 with double period, which should give me a stable solution again, compareable to this example from literature:

How can this be done? I've tried

PCargs.name = 'LC2'
PCargs.initpoint = 'LC1:PD1'
PCargs.period = PyCont['LC1'].getSpecialPoint('PD1')['_T']*2
PyCont.newCurve(PCargs)

PyCont['LC2'].forward()

which is not working, PCargs.period =... seems not to work, PyCont['LC2'].forward() starts with old period in PD1 and therefore LC2 gets identical with LC1. Isn't LC-C working together with PCargs.period? Or is there something not working properly on my system?

As a work-around, I've got the idea to use the parameter-value in PD, do some time integration based on this parameter-value and create an initcycle with correct (double) period. Then initialising continuation in the following way:

PCargs.name = 'LC2'
PCargs.initcycle = cycle2
PyCont.newCurve(PCargs)

PyCont['LC2'].forward()

Continuation now starts with correct period, but the parameter-value is wrong, its the same value as in P1, where bifurcation of the first curve startet.

The last idea is to use a new continuation-class for the second curve. But how can I plot results from different classes in one diagram together?

Hope anyone can help me.

Thank you very much!
Emil