Detect continue event and bifuraction event

[MaxwellDemonLin]

Hi

I want detect continue event and bifuraction event at same time.

bprob, ev1 = get_bifurcation_problem(nw, s0)
ev2 = BifDetectEvent
eve = SetOfEvents(ev1,ev2)
opts = ContinuationPar(p_min = -10.0, p_max = -0.5, newton_options = optnewton, ds = -1e-5, dsmax =1e-1,dsmin=1e-12,max_steps = 5000,detect_event = 2,detect_bifurcation=0,detect_fold = false,
  	tol_stability = 1e-5)

opts = @set opts.newton_options.verbose = false

br = continuation(bprob, PALC(), opts,verbosity = false,event = ev1, bothside = false,finalise_solution = finalise_solution, plot = false)
When I detect ev1 only, it is work

When I detect ev2 only, it is work
br = continuation(bprob, PALC(), opts,verbosity = false,event = ev2, bothside = false,finalise_solution = finalise_solution, plot = false)

br = continuation(bprob, PALC(), opts,verbosity = false,event = eve, bothside = false,finalise_solution = finalise_solution, plot = false)
But wen I detect eve event

It have a fault ┌ Error: Error, no event was characterized whereas one was detected.
│ Please open an issue at https://github.com/rveltz/BifurcationKit.jl/issues.
│ The events are eventValue = (((-2.4291602276246116,), (2,)), ((-2.426647295056616,), (2,)))
└ @ BifurcationKit C:\Users\12251.julia\dev\BifurcationKit\src\events\EventDetection.jl:399

[rveltz]

Sorry about this.

• Can you show the REPL output with verbosity=3 a few steps around the error?
• Can you try PairOfEvents?

[MaxwellDemonLin]

────▶ eve (current) ((-2.4291602245949964,), (2,)) ──▶ ((-2.42916022661474,), (2,))
────▶ eigvals =
236.06639421861377 - 2586.2407290881674im
236.06639421861377 + 2586.2407290881674im
-0.09999781902786803 + 0.0im
-0.31968170566126286 - 1.291324615310913im
-0.31968170566126286 + 1.291324615310913im
-0.5037893150956875 - 0.490482875304352im
-0.5037893150956875 + 0.490482875304352im
────▶ 24 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 1.8543040865705122e-9, p = -4.366362563626805, #reverse = 0
────▶ event ∈ (-4.372735763112464, -4.366362563626805), precision = -6.373E-03
Predictor: Secant

────▶ eve (current) ((-2.42916022661474,), (2,)) ──▶ ((-2.4291602276246116,), (2,))
────▶ eigvals =
236.0663933107328 - 2586.240729951256im
236.0663933107328 + 2586.240729951256im
-0.09999781902600759 + 0.0im
-0.3196817060847701 - 1.2913246135994987im
-0.3196817060847701 + 1.2913246135994987im
-0.503789315827743 - 0.4904828766842191im
-0.503789315827743 + 0.4904828766842191im
────▶ 25 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 9.271520432852561e-10, p = -4.366362561062363, #reverse = 0
────▶ event ∈ (-4.372735763112464, -4.366362561062363), precision = -6.373E-03
────▶ Found at p = -4.366362561062363 ∈ (-4.366362561062363, -4.372735763112464),
δn = 0, from p = -4.452386227965307
────────────────────────────────────────
────▶ Stopping reason:
──────▶ isnothing(next) = false
──────▶ |ds| < dsmin_bisection = false
──────▶ step >= max_bisection_steps = true
──────▶ n_inversion >= n_inversion = false
──────▶ eventlocated = false
────▶ Leaving [location event]
┌ Error: Error, no event was characterized whereas one was detected.
│ Please open an issue at https://github.com/rveltz/BifurcationKit.jl/issues.
│ The events are eventValue = (((-2.4291602276246116,), (2,)), ((-2.426647295056616,), (2,)))
└ @ BifurcationKit C:\Users\12251.julia\dev\BifurcationKit\src\events\EventDetection.jl:399
-3.4986309662668793

And it is work when using PairOfEvents

[rveltz]

Can you show the output starting a bit before entering bisection please?

[MaxwellDemonLin]

It comes from another set of parameters, but same issuse

━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Continuation step 67
Step size = -4.2680e-02
Parameter p141 = -3.9855e+00 ──▶ -4.0449e+00 [guess]
──▶ Step Converged in 5 Nonlinear Iteration(s)
Parameter p141 = -3.9855e+00 ──▶ -4.0449e+00
──▶ Computed 7 eigenvalues in 1 iterations, #unstable = 2
Predictor: Secant
──▶ Event values: ((-0.6726342395193945,), (2,))
──▶ ((-0.6467898928425032,), (2,))
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Continuation step 68
Step size = -4.8015e-02
Parameter p141 = -4.0449e+00 ──▶ -4.1118e+00 [guess]
──▶ Step Converged in 5 Nonlinear Iteration(s)
Parameter p141 = -4.0449e+00 ──▶ -4.1118e+00
──▶ Computed 7 eigenvalues in 1 iterations, #unstable = 2
Predictor: Secant
──▶ Event values: ((-0.6467898928425032,), (2,))
──▶ ((-0.616516910580805,), (2,))
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Continuation step 69
Step size = -5.4017e-02
Parameter p141 = -4.1118e+00 ──▶ -4.1870e+00 [guess]
──▶ Step Converged in 5 Nonlinear Iteration(s)
Parameter p141 = -4.1118e+00 ──▶ -4.1870e+00
──▶ Computed 7 eigenvalues in 1 iterations, #unstable = 4
Predictor: Secant
──▶ Event values: ((-0.616516910580805,), (2,))
──▶ ((-0.5808467498313494,), (4,))
──▶ Event detected before p = -4.187015677452831
────▶ Entering [location event], indicator of 2 last events = (1, 1)
────▶ [Bisection] initial ds = -0.06076949052041462
────▶ [Bisection] state.ds = 0.06076949052041462
──▶ eve (initial) ((-0.616516910580805,), (2,)) ──▶ ((-0.5808467498313494,), (4,))

──▶ eigvals =
193.88775963073715 - 2448.709401051911im
193.88775963073715 + 2448.709401051911im
1.5136302287984336 - 1348.6209452884884im
1.5136302287984336 + 1348.6209452884884im
-0.07056181436102679 - 1.215700367993071im
-0.07056181436102679 + 1.215700367993071im
-0.0999961326568377 + 0.0im

────▶ eve (current) ((-0.5808467498313494,), (4,)) ──▶ ((-0.5808467498313494,), (4,))
────▶ eigvals =
193.88775963073715 - 2448.709401051911im
193.88775963073715 + 2448.709401051911im
1.5136302287984336 - 1348.6209452884884im
1.5136302287984336 + 1348.6209452884884im
-0.07056181436102679 - 1.215700367993071im
-0.07056181436102679 + 1.215700367993071im
-0.0999961326568377 + 0.0im
────▶ 0 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 0.03038474526020731, p = -4.187015677452831, #reverse = 0
────▶ event ∈ (-4.187015677452831, -4.111798551903607), precision = 7.522E-02
Predictor: Secant

────▶ eve (current) ((-0.5808467498313494,), (4,)) ──▶ ((-0.6011279619388785,), (2,))
────▶ eigvals =
180.26054865247886 - 2451.275432053927im
180.26054865247886 + 2451.275432053927im
-0.07290523470607682 - 1.212073080901506im
-0.07290523470607682 + 1.212073080901506im
-0.09999612919719023 + 0.0im
-0.09999844167485163 + 0.0im
-0.13686257229085858 + 0.0im
────▶ 1 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 0.015192372630103654, p = -4.144708102385903, #reverse = 0
────▶ event ∈ (-4.144708102385903, -4.111798551903607), precision = 3.291E-02
Predictor: Secant

────▶ eve (current) ((-0.6011279619388785,), (2,)) ──▶ ((-0.6110587354556531,), (2,))
────▶ eigvals =
173.66642121700386 - 2452.397394508111im
173.66642121700386 + 2452.397394508111im
-0.07404502220999148 - 1.2103072934785508im
-0.07404502220999148 + 1.2103072934785508im
-0.0999961274401139 + 0.0im
-0.09999844627933537 + 0.0im
-0.13686180368628997 + 0.0im
-0.3006691344051329 - 6.404315976523129im
-0.3006691344051329 + 6.404315976523129im
────▶ 2 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 0.007596186315051827, p = -4.123552423573759, #reverse = 0
────▶ event ∈ (-4.123552423573759, -4.111798551903607), precision = 1.175E-02
Predictor: Secant

────▶ eve (current) ((-0.6110587354556531,), (2,)) ──▶ ((-0.6159728896383464,), (2,))
────▶ eigvals =
170.4231201502767 - 2452.9208173446445im
170.4231201502767 + 2452.9208173446445im
-0.07460721009077242 - 1.2094359854818937im
-0.07460721009077242 + 1.2094359854818937im
-0.09999612656499819 + 0.0im
-0.09999844858778807 + 0.0im
-0.13686141561684587 + 0.0im

────▶ 23 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 3.622143895650781e-9, p = -4.102395550925992, #reverse = 0
────▶ event ∈ (-4.111798551903607, -4.102395550925992), precision = -9.403E-03
Predictor: Secant

────▶ eve (current) ((-0.11642862339224536,), (2,)) ──▶ ((-0.11642862398539333,), (2,))
────▶ eigvals =
167.21523356340157 - 2453.4201881456406im
167.21523356340157 + 2453.4201881456406im
-0.07516432835950343 - 1.2085722578149916im
-0.07516432835950343 + 1.2085722578149916im
-0.09999612568009256 + 0.0im
-0.09999845089510141 + 0.0im
-0.13686102547382925 + 0.0im
────▶ 24 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 1.8110719478253906e-9, p = -4.102395545881657, #reverse = 0
────▶ event ∈ (-4.111798551903607, -4.102395545881657), precision = -9.403E-03
Predictor: Secant

────▶ eve (current) ((-0.11642862398539333,), (2,)) ──▶ ((-0.1164286242819671,), (2,))
────▶ eigvals =
167.215232802771 - 2453.4201882618895im
167.215232802771 + 2453.4201882618895im
-0.07516435114418187 - 1.2085722660948246im
-0.07516435114418187 + 1.2085722660948246im
-0.09999612567794913 + 0.0im
-0.09999845089643494 + 0.0im
-0.13686102522386495 + 0.0im
────▶ 25 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
ds = 9.055359739126953e-10, p = -4.1023955433594885, #reverse = 0
────▶ event ∈ (-4.111798551903607, -4.1023955433594885), precision = -9.403E-03
────▶ Found at p = -4.1023955433594885 ∈ (-4.1023955433594885, -4.111798551903607),
δn = 0, from p = -4.187015677452831
────────────────────────────────────────
────▶ Stopping reason:
──────▶ isnothing(next) = false
──────▶ |ds| < dsmin_bisection = false
──────▶ step >= max_bisection_steps = true
──────▶ n_inversion >= n_inversion = false
──────▶ eventlocated = false
────▶ Leaving [location event]
┌ Error: Error, no event was characterized whereas one was detected.
│ Please open an issue at https://github.com/rveltz/BifurcationKit.jl/issues.
│ The events are eventValue = (((-0.1164286242819671,), (2,)), ((-0.11531498330619916,), (2,)))
└ @ BifurcationKit C:\Users\12251.julia\dev\BifurcationKit\src\events\EventDetection.jl:399

[rveltz]

Very strange, there is a bug, #reverse should change. Do you have a MWE? Can you post it?

[MaxwellDemonLin]

It is a MWE.

using Revise, Plots
using BifurcationKit
const BK = BifurcationKit
# vector field of the problem
function COm(u, p)
	(;q1,q2,q3,q4,q5,q6,k) = p
	x, y, s = u
	z = 1-x-y-s

	[
		2q1 * z^2 - 2q5 * x^2 - q3 * x * y,
		q2 * z - q6 * y - q3 * x * y,
		q4 * z - k * q4 * s
	]
end

# parameters used in the model
par_com = (q1 = 2.5, q2 = 0.6, q3 = 10., q4 = 0.0675, q5 = 1., q6 = 0.1, k = 0.4)

recordCO(x, p; k...) = (x = x[1], y = x[2], s = x[3])

# initial condition
z0 = [0.07, 0.2, 05]



function detect_event(iter, state)
    u = getx(state)

    return u[1] - 0.1
end

ev2 = ContinuousEvent(
    1,
    detect_event,
    ("ev2",)
)
ev1 = BifDetectEvent
eve = SetOfEvents(ev2,ev1)
# Bifurcation Problem
prob = BifurcationProblem(COm, z0, par_com, (@optic _.q2); record_from_solution = recordCO)
# continuation parameters
opts_br = ContinuationPar(p_max = 1.9, dsmax = 0.01,detect_event = 2,detect_bifurcation=0)

# compute the branch of solutions
br = continuation(prob, PALC(), opts_br; normC = norminf ,event = ev2,verbosity = 3)

plot(br)

[rveltz]

Thank you!
This seems to work for me:

br = continuation(prob, PALC(), opts_br; normC = norminf ,event = eve, verbosity = 3)

Does it error for you?
What is your BK version?

[MaxwellDemonLin]

br = continuation(prob, PALC(), opts_br; normC = norminf ,event = eve, verbosity = 3)
Not work for me.

Continuation step 29 
Step size = 1.0000e-02
Parameter q2 = 9.9706e-01 ──▶  1.0095e+00 [guess]
──▶ Step Converged in 3 Nonlinear Iteration(s)
Parameter q2 = 9.9706e-01 ──▶  1.0090e+00
──▶ Computed 3 eigenvalues in 1 iterations, #unstable = 0
Predictor:  Secant
──▶ Event values: ((0.008123679566409692,), (0,))
              ──▶ ((0.0016676469133716787,), (0,))
━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━
Continuation step 30 
Step size = 1.0000e-02
Parameter q2 = 1.0090e+00 ──▶  1.0209e+00 [guess]
──▶ Step Converged in 3 Nonlinear Iteration(s)
Parameter q2 = 1.0090e+00 ──▶  1.0203e+00
──▶ Computed 3 eigenvalues in 1 iterations, #unstable = 0
Predictor:  Secant
──▶ Event values: ((0.0016676469133716787,), (0,))
              ──▶ ((-0.005213031788471281,), (0,))
──▶ Event detected before p = 1.020274017271234
────▶ Entering [location event], indicator of 2 last events = (0, 1)
────▶ [Bisection] initial ds = 0.01
────▶ [Bisection] state.ds = -0.01
──▶ eve (initial) ((0.0016676469133716787,), (0,)) ──▶ ((-0.005213031788471281,), (0,))

──▶ eigvals =
-0.04297502227641399 - 0.07095563755170399im
-0.04297502227641399 + 0.07095563755170399im
-6.449406692463641 + 0.0im

────▶ eve (current) ((-0.005213031788471281,), (0,)) ──▶ ((-0.005213031788471281,), (0,))
────▶ eigvals =
-0.04297502227641399 - 0.07095563755170399im
-0.04297502227641399 + 0.07095563755170399im
-6.449406692463641 + 0.0im
────▶ 0 - [Bisection] (n1, n_current, n2) = (1, 0, 0)
                        ds = -0.005, p = 1.020274017271234, #reverse = 0
────▶ event ∈ (1.0090220156839735, 1.020274017271234), precision = 1.125E-02
Predictor:  Secant

────▶ eve (current) ((-0.005213031788471281,), (0,)) ──▶ ((-0.0017348308759555509,), (0,))
────▶ eigvals =
-0.0525198706623914 - 0.06999775547192942im
-0.0525198706623914 + 0.06999775547192942im
-6.41689003041008 + 0.0im
────▶ 1 - [Bisection] (n1, n_current, n2) = (1, 0, 0)
                        ds = -0.0025, p = 1.0147815186136933, #reverse = 0
────▶ event ∈ (1.0090220156839735, 1.0147815186136933), precision = 5.760E-03
Predictor:  Secant

────▶ eve (current) ((-0.0017348308759555509,), (0,)) ──▶ ((-3.413711765677674e-5,), (0,))
────▶ eigvals =
-0.05726156784644693 - 0.06905013279062021im
-0.05726156784644693 + 0.06905013279062021im
-6.401376198763225 + 0.0im



────▶ 23 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
                        ds = -5.960464477539063e-10, p = 1.0521054029885872, #reverse = 0
────▶ event ∈ (1.052101415821629, 1.0521054029885872), precision = -3.987E-06
Predictor:  Secant

────▶ eve (current) ((-0.04377151897466072,), (2,)) ──▶ ((-0.04377151860282305,), (2,))
────▶ eigvals =
0.08489375648810002 + 0.0im
0.002815924075434792 + 0.0im
-6.92253331030286 + 0.0im
────▶ 24 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
                        ds = -2.9802322387695313e-10, p = 1.052105402956439, #reverse = 0
────▶ event ∈ (1.052101415821629, 1.052105402956439), precision = -3.987E-06
Predictor:  Secant

────▶ eve (current) ((-0.04377151860282305,), (2,)) ──▶ ((-0.043771518416904215,), (2,))
────▶ eigvals =
0.08489375562355313 + 0.0im
0.002815924352205713 + 0.0im
-6.922533307270467 + 0.0im
────▶ 25 - [Bisection] (n1, n_current, n2) = (1, 1, 1)
                        ds = -1.4901161193847657e-10, p = 1.052105402940365, #reverse = 0
────▶ event ∈ (1.052101415821629, 1.052105402940365), precision = -3.987E-06
────▶ Found at p = 1.052105402940365 ∈ (1.052105402940365, 1.052101415821629),
                          δn = 0, from p = 1.05193635758396
────────────────────────────────────────
────▶ Stopping reason:
──────▶ isnothing(next)             = false
──────▶ |ds| < dsmin_bisection      = false
──────▶ step >= max_bisection_steps = true
──────▶ n_inversion >= n_inversion  = false
──────▶ eventlocated                = false
────▶ Leaving [location event]
┌ Error: Error, no event was characterized whereas one was detected.
│ Please open an issue at https://github.com/rveltz/BifurcationKit.jl/issues.
│  The events are eventValue = (((-0.043771518416904215,), (2,)), ((-0.04372587357536285,), (2,)))
└ @ BifurcationKit C:\Users\12251\.julia\packages\BifurcationKit\q52qN\src\events\EventDetection.jl:399

My Julia version is v1.11, BK version is v0.5.5

[rveltz]

I can reproduce on Julia v1.10 and v1.11 and on BK#master.
PairOfEvents seems to work, is it enough for you? I dont know how long this fix will take.

[MaxwellDemonLin]

Thank you for your help.

PairOfEvents can partially meet my needs; I can do other work first, but I will need it in the future.