new schedule strategy

src/fit.jl

@@ -453,7 +453,7 @@ end
 
 function train!(ts, nepoch::Number=-1, args...; 
     trainer=trainepoch_EM2!, patient::Number=trainer(:patient), 
-    optimiser=Momentum(η=0.3, ρ=0.5), scheduler=opt->eta!(opt, eta(opt)*0.8),
+    optimiser=Momentum(η=1/4, ρ=0.5), scheduler=lr->lr*√0.5,
     callback=x -> x, reposition=i -> true, resource=trainer(inputs=ts), kargs...)
     reposition_flag = true
     if reposition isa Function
@@ -477,6 +477,7 @@ function train!(ts, nepoch::Number=-1, args...;
     indi_r = MonotoneIndicator{Int}() #for reposition
     indi_g = MonotoneIndicator{Int}() #for global patient
     indi_s = MonotoneIndicator{Int}() #for lr scheduler
+    eta_list = []
     reposition_count = 0.
     last_repositioned = nothing
     colist = nothing
@@ -524,9 +525,17 @@ function train!(ts, nepoch::Number=-1, args...;
             @info "The repositioning strategy failed after $ep epochs"
             break
         end
-        if indi_s.age > max(1, patient, nepoch / 200 * max(1, (length(ts) / indi_g.min)))
-            scheduler(optimiser)
-            @info "@epoch $ep(+$(indi_s.age)) η -> $(round(eta(optimiser), digits=3)) (current $nc collisions, best $(indi_s.min) collisions)"
+        if indi_s.age > max(1, patient, nepoch / 50)
+            if isempty(eta_list) || indi_s.min < eta_list[end][2] || (indi_s.min == eta_list[end][2] && rand()>0.5)
+                _eta = eta(optimiser)
+                push!(eta_list, (_eta, indi_s.min))
+                eta!(optimiser, scheduler(_eta))
+                @info "@epoch $ep(+$(indi_s.age)) η -> $(round(eta(optimiser), digits=3)) (current $nc collisions, best $(indi_s.min) collisions)"
+            else
+                last_eta, last_nc = pop!(eta_list)
+                eta!(optimiser, last_eta)
+                @info "@epoch $ep(+$(indi_s.age)) η <- $(round(eta(optimiser), digits=3)) (collisions $(indi_s.min) ≥ $(last_nc))"
+            end
             reset!(indi_s)
         end
         if indi_g.age > max(2, 2patient, nepoch / 50 * max(1, (length(ts) / indi_g.min)))