Help associating ode events (if they occur?) to plotted symbols and legends

I have identified 4 ode events. The integration stop event which will occur, but the other 3 might not. The events function order list, intended symbol on a graph and accompanying legend are:

n - symbol - legend

1 - 'kx' - 'end' (integration stop)

2 - 'k.' - 'vertex'

3 - 'kv' - 'threshold decreasing'

4 - 'k^' - 'threshold increasing'

If possible, I would basically like to plot something like:

hold on

plot(t,y))

plot(te1,ye1),'symbol1')

plot(te2,ye2),'symbol2') - might not occur

plot(te3,ye3),'symbol3') - might not occur

plot(te4,ye4),'symbol4') - might not occur

hold off

legend(anything,legend1,legend2,legend3,legend4) - later legends might not occur

So far, chronological events in the 'ie' matrix are [3;2;4;1] or [2;3;4;1], but this might change!

Try as i may, i cannot correctly accociate events with plotted symbols or legends, let alone instances where they might not occur!

Any help or advice on how i might achieve this would be greatly appreciated.

[Walter Roberson]

Are you using the 5-output version of ode45 ? Something like

mask = ie == 1;
te1 = te(mask);
ye1 = ye(mask,:);

?

[Brantosaurus]

Yes i believe.

options = odeset('events',@trajevents)

[t,y,te,ye,ie] = ode45(@state,tspan,yo,options)

:

function [check,stop,direction] = trajevents(t,y)

check, stop and direction each contain details which sucessfully trigger the 4 events.

All the workspace outputs look fine and the basic full span plots of [t,y] and 4 discrete [te(ie),ye(ie)].

The plotting of [te(ie),ye(ie)] with symbol and legend associations are the problem even when 4 events occur, which might not always be the case!

The images show what i would like to achieve. The order of events and number can change.

[Walter Roberson]

What difficulty are you encountering? It would probably be easier if you could post code for us to test.

Question: if an event does not occur then should it still appear in the legend?