One way is with the Sims package. I'm not sure I got everything right with your model.
https://tshort.github.io/Sims.jl/ using Sims, Winston function model() # note that the time scale is in hours D = Unknown(10.0, "D") A1 = Unknown("A1") rateConstant1 = 3.0 rateConstant2 = 5.0 @equations begin der(D) = -rateConstant1*D der(A1) = rateConstant1*D - rateConstant2*A1 Event(sin(2pi/12 * MTime), # Initiate an event every 12 hours Equation[ reinit(D, D + 10) # add a dosage of 10 ]) end end x = sim(model(), 60); wplot(x) On Thu, Aug 20, 2015 at 8:36 PM, Martin J <jmalph...@gmail.com> wrote: > Hi all, > > I am trying to use julia ode or sundials for the following simple > differential equation. > > dD = -rateConstant1*D > dA1 = rateConstant1*D - rateConstant2*A1 > > This differential equations explain the disposition of drug in human > system. > > *My question is related to resetting state variable at specified time. * > > In this example, drug was administered repeatedly every 12 hours for 48 > hours. So, I need to add an amount to dD every 12 hour to achieve this. In > R and deSolve package, this repeated addition of dose was achieved by using > ‘events’ options in ode. (R code attached) > > dose.events (please refer R code - line 32) object is presented below: > > var time value method > depot 0 10 replace > depot 12 10 replace > depot 24 10 replace > depot 36 10 replace > depot 48 10 replace > > With my limited understanding, this ‘events’ option in ode (deSolve), > replaces the depot (dD) at these mentioned time with the said value. > > I am looking for similar option in sundials or julia ode. > > Could you please guide me with this ? > > Thanks for your suggestions. > > regards, > Martin >
