Question regarding Calculation Process in $DES BLOCK

From: Li Li Date: May 26, 2011 technical Source: mail-archive.com
Hi, I have a question about calculation process in $DES block. Suppose I have 2 subjects, subject 1 has time point from 0-4hr, subject 2 has time point from 0-5hr. Suppose I have NONMEM codes as follows: $DES DDT1=T DADT(1)=-Kin*A(1) When I output DDT1, the table will be: Subject Time (hr) DDT1 1 0 4??? 1 1 1 1 2 2 1 3 3 1 4 4 2 0 5??? 2 1 1 2 2 2 2 3 3 2 4 4 2 5 5 Why the DDT1 for subject 1 at first time point is 4 and subject 2 at first time point is 5? Why it holds the last time point value of each subject? Thank you. lili