RE: Problem in Simulation

From: Jean Lavigne Date: June 04, 2012 technical Source: mail-archive.com
Dear Mayank, I do not know if it will solve your problem, but I have noticed that the only place where you have '**' in your code is: DADT(1) = -KTR*A(1) + KTR*A(1)*(1-DRUG)*((CIRC0/A(5))**GAM) Since CIRC0 seems fixed to 5.45, it must be A(5) that may get smaller than zero (some time numerical approximation may end up with a very small negative value when the compartment #5 gets empty). In your code you did put some protection when A(5) is less or equal to zero (see the copied code below), so you may want to do the same with DADT(1). IPRED = 0.0001 IF(A(5).GT.0) IPRED = A(5) I hope this will help! Jean
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-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of mayank patel Sent: Monday, June 04, 2012 11:13 AM To: [email protected] Subject: [NMusers] Problem in Simulation Dear NMUSERS, I am trying to simulate ANC using Transit compartment Neutrapenia model. I am simulating for different schedule. I have used this for another drug and it worked fine. But rightnow it gives me error as below. If someone can guide me regarding this problem, it would be helpful. PROBLEM NO.: 1 SUBPROBLEM NO.: 1 0PRED EXIT CODE = 10 INDIVIDUAL NO. 61 ID= 6.10000000000000E+01 (WITHIN-INDIVIDUAL) DATA REC NO. 207 THETA= 5.45E+00 1.35E+02 1.74E-01 2.14E-01 0.00E+00 DES SUBROUTINE: ERROR IN COMPUTATION ATTEMPT TO COMPUTE BASE**POWER WITH BASE<0. MESSAGE ISSUED FROM SIMULATION STEP==== END TIME ==== Fri 06/01/2012 02:09 PM Please find below control stream. If anyone can take a look and advice on that it would be helpful. $PROB ANC Predictions $INPUT C=DROP ID EVID CMT AMT RATE DV TRET TIME DAYS $DATA all_schedules_grid.csv IGN=C $SUBS ADVAN8 TOL=5 $MODEL COMP=(STEM) ;1 COMP=(TRANSIT1) ;2 COMP=(TRANSIT2) ;3 COMP=(TRANSIT3) ;4 COMP=(TRANSIT4) ;5 COMP=(Central) ;6 COMP=(Peri) ;7 $PK "FIRST" USE PRCOM_INT,ONLY:IMAX " MAIN " IMAX=9900000000 CL = 1.14 V1 = 6 K12 = 0.14 K21 = 0.06 K10 = CL/V1 CIRC0 = THETA(1)*EXP(ETA(1)) MTT = THETA(2)*EXP(ETA(2)) KTR = 4/MTT GAM = THETA(3) SLOPE = THETA(4)*EXP(ETA(3)) A_0(1) = CIRC0 A_0(2) = CIRC0 A_0(3) = CIRC0 A_0(4) = CIRC0 A_0(5) = CIRC0 $DES EDRUG = 0 CP=A(6)/V1 IF(TRET.EQ.1.OR.TRET.EQ.3) EDRUG = SLOPE*CP DRUG = EDRUG DADT(1) = -KTR*A(1) + KTR*A(1)*(1-DRUG)*((CIRC0/A(5))**GAM) DADT(2) = -KTR*A(2) + KTR*A(1) DADT(3) = -KTR*A(3) + KTR*A(2) DADT(4) = -KTR*A(4) + KTR*A(3) DADT(5) = -KTR*A(5) + KTR*A(4) ; CIRCULATING CELLS DADT(6) = -K10*A(6) -K12*A(6) +K21*A(7) DADT(7) = -K21*A(7) +K12*A(6) $ERROR IPRED = 0.0001 IF(A(5).GT.0) IPRED = A(5) W = THETA(5)*IPRED IRES = DV - IPRED IWRES = IRES/W Y = IPRED+W*EPS(1) REP=IREP AA9 = A(6)/V1 $THETA 5.45 FIX ;1 BASE $THETA 135 FIX ;2 MTT (h) $THETA 0.174 FIX ;3 POWER $THETA 0.2141 FIX ;4 SLOPE $THETA 0 FIX; (.554 ) ;7 Res err $OMEGA 0.168 FIX ;1 IIV CIRC0 $OMEGA 0.0256 FIX ;2 IIV MTT $OMEGA 0.36 FIX ;3 IIV SLOPE $SIGMA 0 FIX ;1 FIX $SIM (889215690) ONLYSIM SUBPROBLEM = 5 $TABLE REP ID TIME TRET DAYS CP EVID IPRED CIRC0 MTT GAM SLOPE NOPRINT NOHEADER FILE=ResultANC.tab Schedule file: C 24.7143mg_1on-0off C ID Evid CMT AMT RATE DV TRET TIME DAYS 1 0 5 0 0 . 3 0 0 1 1 6 24.71 24.71 . 3 0 0 1 0 5 0 0 . 3 12 0.5 1 0 5 0 0 . 3 24 1 1 1 6 24.71 24.71 . 3 24 1 1 0 5 0 0 . 3 36 1.5 Mayank PatelPh.D Student, Long Island University, NY This electronic transmission may contain confidential and/or proprietary information and is intended to be for the use of the individual or entity named above. If you are not the intended recipient, be aware that any disclosure, copying, distribution or use of the contents of this electronic transmission is prohibited. If you have received this electronic transmission in error, please destroy it and immediately notify us of the error. Thank you.
Jun 04, 2012 Mayank Patel Problem in Simulation
Jun 04, 2012 Jean Lavigne RE: Problem in Simulation
Jun 04, 2012 Mario Gonzalez RE: Problem in Simulation
Jun 04, 2012 Peter Bonate RE: Problem in Simulation
Jun 04, 2012 Luann Phillips Re: Problem in Simulation
Jun 05, 2012 Mayank Patel Re: Problem in Simulation
Jun 05, 2012 Mayank Patel Re: Problem in Simulation