NM: subproblem dependent on Y can't allow me to assign value from a previous time to a current one

[AMCasablancas]

I'm currently trying to get a column on my $TABLE that records the values of the Y for the previous time point for each individual (the sort of data management that you'd do on R) with the ouput of my model.

Something like this:
ID | TIME | YCUR | YPRED | Y
1 | 0.00 | 0.00 | 0.00 | -1
1 | 1.00 | 1.50 | 0.00 | 1.5
1 | 2.00 | 3.50 | 1.50 | 3.5
1 | 3.00 | 7.00 | 3.50 | 7.0

The reason for it is to establish a right-censoring based on the condition that Y goes below a certain value AND the YCUR > YPRED (the beaviour is already in terminal phase). But I don't really know how to do this

This is my code so far:

$PK
IF(NEWIND.NE.2)THEN
    YCUR = 0 
ENDIF

$ERROR
IF(TIME.GT.0) YCUR = Y

Hopefully you could help me with it :)
Thanks

[kylebaron]

Hi @AMCasablancas -

is this what you are looking for?

library(mrgsolve)
#> 
#> Attaching package: 'mrgsolve'
#> The following object is masked from 'package:stats':
#> 
#>     filter

code <- '
$PARAM CL = 5, V = 10

$PKMODEL cmt = "CENT"

$TABLE
if(NEWIND <=1) double PREV = 0;
capture Y = CENT/V;
capture YPREV = PREV;
PREV = Y;
'

mod <- mcode("prev", code)
#> Building prev ...
#> done.

mrgsim(mod, events = ev(amt = 100))
#> Model:  prev 
#> Dim:    26 x 5 
#> Time:   0 to 24 
#> ID:     1 
#>     ID time    CENT       Y   YPREV
#> 1:   1    0   0.000  0.0000  0.0000
#> 2:   1    0 100.000 10.0000  0.0000
#> 3:   1    1  60.653  6.0653 10.0000
#> 4:   1    2  36.788  3.6788  6.0653
#> 5:   1    3  22.313  2.2313  3.6788
#> 6:   1    4  13.534  1.3534  2.2313
#> 7:   1    5   8.208  0.8208  1.3534
#> 8:   1    6   4.979  0.4979  0.8208

^{Created on 2022-12-07 with reprex v2.0.2}

Kyle