st: problem with function evaluator program in nl comand

[Miguel Ampudia Fraile <mampudia@bu.edu>]

Dear all,

I want to use a function evaluator program within the nl command to do
an estimation but I keep getting an error message saying to check
whether my program is a function evaluator program.
I have taken my program to the simplest case possible and I have
followed the examples in the help file step by step. And I keep
getting the same error. Any help would be much appreciated. Here is my
code:

capture program drop nlweight4
program nlweight4

	version 11
	syntax varlist (min=2 max=2)[aw fw iw] if, at(name)
	local assetsinstock : word 1 of `varlist'
	local logincome : word 2 of `varlist'

	tempname A beta1
                scalar `A' = `at'[1,1]
	scalar `beta1' = `at'[1,2]

	replace `assetsinstock' = `A' +`beta1'*`logincome' `if'

end

And then I run:

nl weight4 @ assetsinstock logincome, {parameters(A beta1)} initial(A
1 beta1 1 )


Best,

Miguel
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