Harry Dankowicz

Frequency Response Plots using COLL/PO toolbox

Updated po utilities and demos to handle tangent vectors correctly. Fixed bug in mvdP files.

Updated coll restart constructors, utilities, and demos to handle tangent vectors correctly.

Updated ep_construct_tst with event handler to store SN eigenvector also when not detected as fold point: Modified ep_read_solution accordingly. Updated constructors to properly handle tangent vector stored with solution file. Tentatively updated restart constructors to allow for a -no-pars option in the event that one wishes to reconstruct without adding continuation parameters. This is necessary if constructing multiple instances from stored solutions.

Hi Jonathan, The tbp array contains the time stamps for the basepoint mesh. Assuming that you use adaptation (i.e., with NAdapt greater than 0), this is not uniformly distributed, as the algorithms redistribute the mesh to capture areas of greater variability in the solution. To obtain a uniformly distributed time array, use interpolation. I recommend interpolation using the continuous piecewise-smooth polynomial approximant that COCO assumes when discretizing the trajectory segment. Such interpolation...

Hello Jonathan, There are two ways to have user-defined data appear in the bd array: either by appending such data using a slot function that responds to the bddat signal or by adding continuation parameters. For example, the po toolbox defines several slot functions for the bddat signal that add the Floquet multipliers and norms of the solution to the bd array. The function po_add_bddat (as explained in the GettingStartedWithCOCO tutorial) can be used to create such a slot function. The function...

Hi Marc, By design, the function defined in the fourth argument of ep_add_bddattakes three input arguments, the last two of which correspond to the state vector and vector of problem parameters for an equilibrium point. The first argument is not used in the example that you are referring to (but is required syntactically). We could have written prob = ep_add_bddat(prob, '', 'svds', @(~,x,p) min(svds(feval(F('x'),x,p)))); to make that clear. By analogy, the function defined in the fourth argument...

coll and po: corrected use of VAR for restarting from branch of Hopf bifurcations.