## Getting Started Example for PROC TMODEL

```/*--------------------------------------------------------------

SAS Sample Library

Name: tmogs.sas
Description: Example program from SAS/ETS User's Guide,
The TMODEL Procedure
Title: Getting Started Example for PROC TMODEL
Product: SAS/ETS Software
Keys: nonlinear simultaneous equation models
PROC: TMODEL
Notes:

--------------------------------------------------------------*/

data soln;
keep exprun t x y;
length exprun \$ 8;
array experno[4] \$ _temporary_ ( "one" "two" "three" "four" );
call streaminit (1);
do i = 1 to 4;
exprun = experno[i];
do t = 0 to 5 by 0.1;
/* analytic solution for the ODE system */
x = 1/2*(exp(-3*t) - exp(-t)) + rand('normal',0,0.01);
y = 1/2*(exp(-3*t) + exp(-t)) + rand('normal',0,0.01);
output;
end;
end;
run;

proc model outmodel=ode;
endo x y;
parms a b;
g = exp (x + y);
dert.x = -a*x - log (g);
dert.y = -b*y - log (g);
quit;

proc model data=soln model=ode;
fit / time=t dynamic;
quit;

proc tmodel data=soln model=ode;
crosssection exprun;
fit / time=t dynamic;
quit;

data d;
length cs \$ 8;
array csname{5} \$ _temporary_ ( 'first' 'second' 'third' 'fourth' 'fifth' );
call streaminit (1);
do pp = 1 to dim(csname);
lagx = 0;
do t = 1 to 10;
x = 0.8*lagx + rand('normal');
lagx = x;
cs = csname[pp];
output;
end;
end;
run;

proc tmodel data=d;
endo x;
crosssection cs;
parms p;

x = p*lag(x);
fit;
quit;

```