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nlmixrdevelopment / nlmixr

nlmixr: an R package for population PKPD modeling
https://nlmixrdevelopment.github.io/nlmixr/
GNU General Public License v2.0
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time varying parameters #526

Closed snailittle closed 3 years ago

snailittle commented 3 years ago

How do I define a clearance that changes with time: I am trying to implement this function in "fo" or "saem" so that Clearance decrease over time to near 0: 

CL=tvCL * exp(-Kdes*time) * exp(ETA.CL)
mattfidler commented 3 years ago

Both can be supported. You can use the above expression in focei

If you want to use this in saem:

CLa = exp(tvCL+ ETA.CL)
...
CL = exp(-Kdes * time) * CLa