In the simplified NLIN example below, giving initial values to model parameters in the PARAMETER statement is NOT equivalent to specifying them in a dataset. It looks like parameter names are not known at the time of array definitions when the parameters are given in a dataset. Is this an undocumented "feature"?
/* Parameter array given initial values in PARAMETER statement. Works fine. */
proc nlin data=sashelp.class;
parameters w=1 h=1;
bounds w h >= 0;
array x{*} weight height;
array y{*} w h;
s = 0;
do i = 1 to dim(x);
s = s + x{i}*y{i};
end;
model age = s;
run;
/* Same problem. Parameter array given initial values in PDATA dataset. Doesn't work. */
data pd;
Parameter="w"; Estimate=1; output;
Parameter="h"; Estimate=1; output;
run;
proc nlin data=sashelp.class;
parameters / pdata=pd;
bounds w h >= 0;
array x{*} weight height;
array y{*} w h;
s = 0;
do i = 1 to dim(x);
s = s + x{i}*y{i};
end;
model age = s;
run;
ERROR: The variable y was referenced but not given a value.
Are you ready for the spotlight? We're accepting content ideas for SAS Innovate 2025 to be held May 6-9 in Orlando, FL. The call is open until September 25. Read more here about why you should contribute and what is in it for you!
ANOVA, or Analysis Of Variance, is used to compare the averages or means of two or more populations to better understand how they differ. Watch this tutorial for more.
Find more tutorials on the SAS Users YouTube channel.