Sheng: This seems like a rather arbitrary occurrence. If you would supply me with your problem (control stream file and data set), I would be happy to determine if there is a bug. Please let me know what version of NONMEM you are using, compiler, and operating system.
Robert J. Bauer, Ph.D. Vice President, Pharmacometrics, R&D ICON Development Solutions 7740 Milestone Parkway Suite 150 Hanover, MD 21076 Tel: (215) 616-6428 Mob: (925) 286-0769 Email: robert.ba...@iconplc.com<mailto:robert.ba...@iconplc.com> Web: www.iconplc.com<http://www.iconplc.com/> From: owner-nmus...@globomaxnm.com [mailto:owner-nmus...@globomaxnm.com] On Behalf Of Navin Goyal Sent: Tuesday, July 29, 2014 6:25 PM To: Gerry Sheng Cc: nmusers Subject: Re: [NMusers] Simulation problem of normal distributed data Hi Sheng, I don't know the exact reason behind such mysterious behavior but if you just change the seed number (the UNIFORM seed) it works. e.g. I changed the seed# from 7545 to 17545 and was able to simulate 1000 rows for the subject. $SIMULATION (6446) (17545 UNIFORM) ONLYSIM NOPRED SUB=1 Its a rare occurrence but may be the seed number caused some issue (while generating sufficient samples to satisfy the constraints you set up using the DOWHILE LOOP). For example I think the same seed number (7545) may work when the DOWHILE condition is reversed (RL .LT. PRN) however it may not be appropriate based on your problem. .......or may be there is some other explanation to such occurrence. Kind regards Navin Goyal On Tue, Jul 29, 2014 at 10:54 AM, Gerry Sheng <shen...@gmail.com<mailto:shen...@gmail.com>> wrote: Dear NMuser, I encountered a strange problem when I used the following code to simulate normal distributed data. When the data records >797, no result appears with NONMEM run into an infinite loop . But when the records decreasing to 796 (delete the last row), the results will occurred immediately. Anyone else met this phenomenon? Any comments and suggestions are appreciated. Thank you in advance. $PROBLEM PD $INPUT ID,CONC,DV $DATA data.csv IGNORE=@ ; $PRED NMEAN=THETA(1)+ETA(1) SD=THETA(2) ;Simulate count IF (ICALL.EQ.4) THEN N=0 PRN=0 CALL RANDOM(2, R) RL=1-R DO WHILE (RL .GT. PRN) LNNOR=LOG(6.283185)+2*LOG(SD)+((N-NMEAN)/SD)**2 PY=EXP(-0.5*LNNOR) PRN=PRN+PY IF (PRN .LT. RL) N=N+1 ENDDO DV=N ENDIF $THETA (30,41.7,60) ;MEAN (2,14.4,50) ;SD $OMEGA 0 FIX ;MEAN $SIMULATION (6446) (7545 UNIFORM) ONLYSIM NOPRED SUB=1 $TABLE ID TIME DV ONEHEADER NOPRINT FILE=npctab1.dta data.csv like this ID CONC DV 1 0 . 1 0 . 1 0 . 1 0 . 1 0 . 1 0.01 . 1 0.01 . 1 0.01 . 1 0.01 . 1 0.01 . ..... Yucheng Sheng Research Associate School of Pharmacy, UCL -- Navin Goyal <br /><br /> ICON plc made the following annotations. ------------------------------------------------------------------------------ This e-mail transmission may contain confidential or legally privileged information that is intended only for the individual or entity named in the e-mail address. If you are not the intended recipient, you are hereby notified that any disclosure, copying, distribution, or reliance upon the contents of this e-mail is strictly prohibited. If you have received this e-mail transmission in error, please reply to the sender, so that ICON plc can arrange for proper delivery, and then please delete the message. Thank You, ICON plc South County Business Park Leopardstown Dublin 18 Ireland Registered number: 145835
