$PROB THEOPHYLLINE ORAL
$INPUT ID AMT=DROP TIME DV BWT
$DATA ../THEO
$PRED	
  DOSE = 320
  KA   = THETA(1)*EXP(ETA(1))
  V    = THETA(2)*EXP(ETA(2))
  K    = THETA(3)*EXP(ETA(3))
  F    = DOSE/V*KA/(KA - K)*(EXP(-K*TIME) - EXP(-KA*TIME))
  Y    = F + F*EPS(1) + EPS(2)

$THETA (0, 2) (0, 50) (0, 0.1) 
$OMEGA BLOCK(3)
  0.2
  0.1  0.2
  0.1  0.1  0.2
$SIGMA 0.1  0.1
$EST MAX=9999 METHOD=ZERO POSTHOC
$COV PRINT=ERS
$TAB ID ETA(1) ETA(2) ETA(3) NOAPPEND FIRSTONLY
