$PROBLEM One-compartment IV bolus PK model
$INPUT ID TIME DV AMT MDV EVID
$DATA ../data.csv IGNORE=@

$SUBROUTINES ADVAN1 TRANS2

$PK
  TVCL = THETA(1)
  TVV  = THETA(2)

  CL = TVCL * EXP(ETA(1))
  V  = TVV  * EXP(ETA(2))

  S1 = V

$ERROR
  IPRED = F
  W = IPRED * THETA(3)
  IF(W.EQ.0) W = 1
  IRES = DV - IPRED
  IWRES = IRES / W
  Y = IPRED + W * ERR(1)

$THETA
  (0, 5.0)    ; CL (L/h)
  (0, 50.0)   ; V (L)
  (0, 0.10)   ; Proportional error

$OMEGA BLOCK(2)
  0.09        ; IIV CL (CV ~30%)
  0.03 0.0625 ; IIV V (CV ~25%)

$SIGMA
  1 FIX       ; Proportional residual

$ESTIMATION METHOD=1 INTER MAXEVAL=9999 PRINT=10 NOABORT
$COVARIANCE PRINT=E

$TABLE ID TIME IPRED IWRES CWRES NOPRINT ONEHEADER FILE=sdtab001