Re: Generating Cmax at end of infusion

Hi Jeroen, The part of the manual that you described did not mention that the call to ERROR is done. And indeed, you can use MTIME in any subsequent calls to ERROR (that are made at event times). So I do not think this is a bug. Since call to PK is done, you can try to get A() value in the PK block, something like $PK ... C=A(*)/V1 IF(C.GE.CMAX) THEN TMAX=TSTATE CMAX=C ENDIF ... If the end-of-infusion concentration is CMAX, this code may get it out (and TMAX should point to the end-of-infusion; both of them should be taken from the first event record following the end-of-infusion) but I have not tried it. ----------- Here is the part of the manual that discussed use of A(*) in the PK block: A(n) TSTATE A(n) are the latest computed compartment amounts, and TSTATE is the time at which they were computed. That is, A(n) are the amounts at the previous event time, or if at a later time, but before the time for which PK is being called, a lagged or additional dose was given, or a regular infusion was terminated, or a modeled event occurred, then A(n) are the amounts at the latest such time. If there are population etas, and A(n) are used in the $PK abbreviated code, then any $OMEGA records referring to etas explicitly used in this code should precede the $PK record, or if an $MSFI record is used, it should precede the $PK record and include the option NPOP=m. ------------------- Could someone explain why "If there are population etas, and A(n) are used in the $PK abbreviated code, then any $OMEGA records referring to etas explicitly used in this code should precede the $PK record" Thanks Leonid -------------------------------------- Leonid Gibiansky, Ph.D. President, QuantPharm LLC web: www.quantpharm.com e-mail: LGibiansky at quantpharm.com tel: (301) 767 5566 Elassaiss - Schaap, J. (Jeroen) wrote: > Hi Douglas, Paul, > > The help on mtime suggests that it should work. > > " When the time is reached, indicator variables > are set and a call to PK is made. At this call (and/or subsequent to > this call) PK or DES or AES or ERROR can use the indicator variables > to change some aspect of the system, e.g., a term in a differential > equation, or the rate of an infusion. This feature may be used with > any ADVAN routine. " > > The following code (tested with nm6.2.0) however does not work in the $ERROR block, where the model predictions are available. As one can see, CP is only set at the data time event, not at the MTIME. CP2 is not set at all. So it seems $ERROR is not called upon the MTIME event. An indicator in $PK works properly (tested, not shown). Can anyone confirm this behavior? If so, this looks like a bug to me. Best regards, > > Jeroen > > ____model____ > > $PROB structural model 1comp.rep single subject > $INPUT ID TIME DV AMT EVID TRT > $DATA iv_ss.csv IGN=I > $SUBR ADVAN1 TRANS2 > > $PK > > TVCL=THETA(1) > CL=TVCL > TVV=THETA(2) > V=TVV > > S1=V/1000 ;mtime piece > > MTIME(1)=.075 ; .075 h not in dataset > MTIME(2)=.5 ; .5 h not in dataset > IF(TIME.EQ.0)CP=0 > IF(TIME.EQ.0)CP2=0 > > $ERROR > > IPRED=F > Y=F+F*ERR(1) > IF(TIME.EQ.0)MYFLAG=0 ; 0 h IN dataset > IF(MPAST(1).EQ.1.AND.MYFLAG.EQ.0)THEN > CP=F > MYFLAG=1 > ENDIF > > CP2=CP2+MNEXT(2)*F $THETA > > (0,10) > (0,1) > > $OMEGA > > .05 > > $SIM (123456789) > > $EST PRINT=1 MAXEVAL=9990 SIG=3 NOABORT METHOD=0 > ;$COV PRINT=E > $TABLE ID TIME CP CP2 IPRED > NOPRINT ONEHEADER FILE=1cmp.txt > > ____dataset___ > > ID,time h,conc nM,amt,evid,dose æmol > 1,0,.,30,1,10 > 1,0.05,0,.,0,10 > 1,0.166666667,0,.,0,10 > 1,0.333333333,0,.,0,10 > 1,0.683,0,.,0,10 > 1,1,0,.,0,10 > 1,2,0,.,0,10 > 1,4,0,.,0,10 > 1,8,0,.,0,10 > ____table file_____ > > TABLE NO. 1 ID TIME CP CP2 IPRE DV 1.0000E+00 0.0000E+00 0.0000E+00 0.0000E+00 3.2044E+04 0.0000E+00 1.0000E+00 5.0000E-02 0.0000E+00 0.0000E+00 1.9459E+04 1.6272E+04 1.0000E+00 1.6667E-01 6.0768E+03 0.0000E+00 6.0768E+03 7.7936E+03 1.0000E+00 3.3333E-01 6.0768E+03 0.0000E+00 1.1524E+03 1.0149E+03 1.0000E+00 6.8300E-01 6.0768E+03 0.0000E+00 3.5213E+01 2.8321E+01 1.0000E+00 1.0000E+00 6.0768E+03 0.0000E+00 1.4905E+00 1.5249E+00 1.0000E+00 2.0000E+00 6.0768E+03 0.0000E+00 6.9328E-05 7.8605E-05 1.0000E+00 4.0000E+00 6.0768E+03 0.0000E+00 1.4999E-13 1.5736E-13 1.0000E+00 8.0000E+00 6.0768E+03 0.0000E+00 7.0211E-31 6.9514E-31 > > ------------------------------------------------------------------------ > > *From:* [email protected] [ mailto: [email protected] ] *On Behalf Of *Eleveld, DJ > > *Sent:* Tuesday, 06 April, 2010 20:22 > *To:* [email protected]; [email protected] > *Subject:* RE: [NMusers] Generating Cmax at end of infusion > > Hi, > > As others have suggested making an additional record at the known desired time is probably the most straightforward manner to get what you want. So this should probably be a preferred solution. > > If you for some reason you cant to add a record (maybe you dont know the time beforehand), I think you can achieve what you want using MTIME(). This has the added advantage of working without going the $DES route and the associated slower run-times. I'll see if I can get something like that to work tomorrow, just as an excercise. Can the experts give an opinion as to whether MTIME() should work or not? > > Regards, > > Douglas Eleveld >