Bioequivalence and Bioavailability Forum • Package-free solution

Package-free solution [PK / PD]

posted by ElMaestro – Denmark, 2013-07-17 23:53 (4373 d 22:52 ago) – Posting: # 11006
Views: 23,013

Hi John,

Here's an offer of a quick and dirty package-free approach to yung-jin's dataset:

Conc=function(D, K01, K10, V, t, tlag)

{

 C = ((D*K01)/(V*(K01-K10))) * (exp(-K10*(t-tlag)) - exp(-K01*(t-tlag)))

 return(C)

}



Cx=Conc(100, 1.67, 0.213, 10, 6, 0.5)

Cx ## this is the known!

##Let's assume we know D, K01, V, tlag

##We want to find a K10 that gives this result Cx at the given t.



K01_fubar=function(K01start, K01end, Gridsize)

{

 tmpK01=K01start

 hotK=K01start

 minDiff=123456789e54321

 d=(K01end-K01start)/Gridsize

 for (i in 1:Gridsize)

   {

   if (abs(Cx-Conc(100, tmpK01, 0.213, 10, 6, 0.5))<minDiff)

    {

      minDiff=abs(Cx-Conc(100, tmpK01, 0.213, 10, 6, 0.5))

      hotK=tmpK01

    }

   tmpK01=tmpK01+d

   }

 return(hotK) 

}



Solution=K01_fubar(0.001, 10.0, 10000)

Solution

##want more decimals?? the interval above had a grid denisty of (10.0-0.001)/10000 so...

d=(10.0-0.001)/10000

Solution=K01_fubar(Solution-d, Solution+d, 10000)

Solution

—
Pass or fail!
ElMaestro

Complete thread:

1 compartment model with lag time jag009 2013-07-17 15:58
- solve for k01? Helmut 2013-07-17 16:08
  - solve for k01? jag009 2013-07-17 16:19
    - solve for k01? ElMaestro 2013-07-17 17:09
    - no closed form Helmut 2013-07-17 23:01
- 1 compartment model with lag time yjlee168 2013-07-17 20:57
- Package-free solutionElMaestro 2013-07-17 21:53
  - Package-free solution yjlee168 2013-07-17 22:11
    - Package-free solution ElMaestro 2013-07-17 22:27
      - Package-free solution yjlee168 2013-07-17 22:42
  - Package-free solution ElMaestro 2013-07-17 23:21
    - A new R-King was born d_labes 2013-07-18 08:45
      - Brent ElMaestro 2013-07-18 09:07
      - A new R-King was born yjlee168 2013-07-18 10:21
        
        OT: TTT in bear Helmut 2013-07-18 20:28
        
        OT: TTT in bear yjlee168 2013-07-18 22:17
        
        OT: TTT subtleties d_labes 2013-07-19 09:47
        
        OT: TTT subtleties yjlee168 2013-07-20 19:44
        
        OT: beyond TTT? Helmut 2013-07-21 00:08
        
        OT: beyond TTT? yjlee168 2013-07-22 13:45
        
        OT: keep TTT! Helmut 2013-07-22 14:21
        
        OT: keep TTT! yjlee168 2013-07-22 23:42
        
        OT: EOD (here) Helmut 2013-07-23 01:06
    - Package-free solution yjlee168 2013-07-18 10:27
      - Thank you guys! jag009 2013-07-18 16:37
        
        Thank you guys! ElMaestro 2013-07-18 18:57
        
        Thank you guys! jag009 2013-07-19 20:40