Allow changing reaction rate in MassActionJumps about jumpprocesses.jl HOT 4 CLOSED

Each MassActionJump can have either a rate parameter or an index. However, dispatching on Int sounds like a source of chaos, so maybe it can be an easy switch to flip.

from jumpprocesses.jl.

using Catalyst, DiffEqBase, DiffEqJump
 rn = @reaction_network begin
           α, S + I --> 2I
           β, I --> R
         end α β
p = [.1/1000, .01]
tspan = (0.0,250.0)
u0 = [999,1,0] 
dprob = DiscreteProblem(rn,u0,tspan,p)
jprob = JumpProblem(rs, dprob, Direct())
sol = solve(jprob, SSAStepper())

# change the rate of the first reaction
jprob.massaction_jump.scaled_rates[1] = .001
sol = solve(jprob, SSAStepper())

See discussion at https://discourse.julialang.org/t/simulating-mjps-many-times-with-different-parameters-as-inner-loop/49061/11 too.

from jumpprocesses.jl.

This probably needs some type of API accessor for easier updating, and which can work within callbacks too.

from jumpprocesses.jl.

This could be handled by having MassActionJump's take an optional extra parameter vector: rate_idxs_in_params or such. Then when the JumpProblem is constructed the corresponding parameter from prob.p could be used instead.

Only took three years for me to implement this, but should be fixed by #190.

from jumpprocesses.jl.