Remove matrix optional parameter from ProportionalIntegralLoop. Always use the matrix method as the formuma method does not give results as good as the matrix method (leads to voltage/phase oscillations).

Fix lcbi_growth_rate_mode, effective_impedance and head_tail_form_factor to be use new form of eta.

Add new ig_phasor_record attribute to CavityResonator, non zero only when specific FB type are used.
Monitor ig_phasor_record with CavityMonitor.
Modify plot_cavitydata to allowing plotting of ig_phasor_record.

Add Synchrotron.get_longitudinal_twiss method to compute the longitudinal Twiss parameters and the synchrotron tune for single or multi-harmonic RF systems.
Change back synchrotron_tune to provide only the usual the (unperturbed) synchrotron tune from main RF voltage.
The longitudinal invariant Js is now computed in Bunch.cs_invariant and Beam.bunch_cs and save by BeamMontior and BunchMonitor, its value is 0 by default if the longitudinal Twiss parameters are not provided in the Synchrotron class.

Synchrotron.synchrotron_tune can now compute the synchrotron tune for single or multi-harmonic RF systems using linear approximation.

Fix wrong sign of the longitudinal wake in LongRangeResistiveWall, thanks to Keon Hee Kim for pointing this out.
Fix ImpedanceModel.add method to raise error before making modifications.

Add ProportionalIntegralLoop and DirectFeedback based on a code refactoring of the RF-FB branch of Naoto.
Small changes to ProportionalLoop and TunerLoop to store the cav_res as class attribute to agree with other FBs.
Small change to the CavityResonator.feedback interface.

Add an interface in CavityResonator to allow for external FB and loops.
Add the ProportionalLoop and TunerLoop using what was already done in the RF-FB branch.

Also change CavityMonitor and plot_cavitydata to record and display generator_phasor_record data.

for spectral_density()
- Corrected Hermite mode to include normalisation by the mode number
- some authorefactoring

 modes to effective impedance computation
 -  for transverse plane modes, the frequency sampling should be
 with fractional part of the transverse tune.
 Otherwise code does not work for single bunch case (M=1)
 - added head_tail_form_factor(), a function that computes only
  the denominator of the effective impedance.
  To be used to compute tune shifts in low intensity approximation
  - added tune_shift_from_effective_impedance() to implement it
  in the future
  - some autorefactoring

Add optional output for read_IW2D, read_IW2D_folder and read_ABCI
For read_ABCI, skip the longxdip and longydip cases as they are not implemented yet

Can be used to compute the bunch standard deviations and share it between the different bunches.

Change the default binning for WakePotential to 80 (better value for most cases).

np.float and np.complex are deprecated since NumPy 1.20.

Add mcf_order optional parameter for Synchrotron class to prodivde higher-orders momentum compaction factor.
Add Synchrotron.get_mcf_order method to compute momentum compaction factor up to 3rd order from AT lattice.
Modify Synchrotron.eta to use higher order mcf.
Improve Synchrotron docstrings.
Change LongitudinalMap to use Synchrotron.eta.

Calculation was wrong for off center beams.

Add monopolar component to WakeField and WakePotential class.

Now works correctly for up to date version of seaborn.

 with monopolar and dipolar components together.
 The longitudinal dipolar component is not saved.

Merge branch 'develop' of https://gitlab.synchrotron-soleil.fr/PA/collective-effects/mbtrack2 into develop

1) group_attributes() will group attributes in the impedance model.
A group can be formed from a list of elements.
This list can be autogenerated by a matching string
2) rename_attribute() simple wrapper to rename an attribute.
Can be used to rename impedance model components.

Correct FIRDamper docstring.

Add version number

Now same as in get_wakepotential

Sections with rho=0 are not considered in resistive_wall_effective_radius any more.
Add a plot_resistivity method.

Fix a hard coded value of  0.5 A ...

Added class representation for ComplexData, Impedance, WakeFunction, WakeField and Beam classes.
Rework the deconvolution/from_wakepotential/to_impedance methods for them to work with any data loaded in the Impedance/WakeFunction classes and not just CST text files.
Add a plot method for the Impedance/WakeFunction classes.
Improved WakeField class by adding __iter__ and __add__ methods.
Add a read_ECHO2D function.

The ImpedanceModel class can now deal with "global impedance" such a resistive wall in addition to do the beta weigthing for "localized" impedances.
The summed wake function after beta weigthing is now normalized by the tracking beta function (ring.optics.local_beta).