Viktor Thunell

Hi, I wish to follow a branching point (BP) in two parameters but I cant figure out how to do this. A colleague of mine has an earlier version (6p2) of MatCont in which he can choose Type > Curve > Branch point (codim 1). Using this option he can follow a branch point in 2 parameters. However, this option seem to have been removed, Its not in my version (6p6) or in later or older versions availabe at Sourceforge. In my version, initializing a BP_BP requires choosing exactly three free parameters...

Hi all, I am having trouble deleting a user function that has been defined incorrectly and therefore prevents me from running my model. I have tried to delete it in the GUI and directly in the system .m -file, but they reappear after I open up the user function GUI again (but only in the .m - file ). This applies to all user functions I define and one solution is to reenter my system. However, this can be very time-consuming as I sometimes make mistakes when entering systems and in this case defining...

Hi all, I am having trouble deleting a user function that has been defined incorrectly and therefore prevents me from running my model. I have tried to delete it in the GUI and directly in the system .m -file, but they reappear after I open up the user function GUI again (but only in the .m - file ). This applies to all user functions I define and one solution is to reenter my system. However, this can be very time-consuming as I sometimes make mistakes when entering systems and in this case defining...

Hi All, I have three general question on analysis of limit cycles in MatCont. When assessing the stability of a limit cycle I understand that the first Lyapunov coefficent (FLC) can be used; a negative FLC corresponds to a supercritical or stable limit cycle and a positve FLC av subcritical or unstable limit cycle. Is this enough to be certain of stability or do I need further "proof" (like the values of the multipliers)? If I continue an equilbrium curve after reaching a Hopf bif. point, will MatCont...

Thank you Hil for your quick response! As I interpret your answer, the following statements of my system is true: The equilibrium that I continue beyond the Hopf point is an unstable steady state (the center of my limit cycle) as my eigenvalues beyond the Hopf point is both negative and positive. The limit cycle born from the Hopf point is stable as it has a negative first Lyapunov coeffeicient and when I continue my limit cycle to asses its stability I conclude that it is stable over my parameter...

Hi All, I have three general question on analysis of limit cycles in MatCont. When assessing the stability of a limit cycle I understand that the first Lyapunov coefficent (FLP) can be used; a negative FLP corresponds to a supercritical or stable limit cycle and a positve FLP av subcritical or unstable limit cycle. Is this enough to be certain of stability or do I need further "proof" (like the values of the multipliers)? If I continue an equilbrium curve after reaching a Hopf bif. point, will MatCont...