st: Program and syntax error "weights not allowed"

[<alvine.bissery@chu-lyon.fr>]

Dera Stata list,

I've a problem with this program.
It seems not possible to replace a value in tata vector.
Could someone explain me ?
How can I do ?

gen tata=0
forvalues i=1/34290 {
local J=nb_exam[`i']
forvalues j=2/`J' {
replace tata[`i']=1 if (date_presc1[`i']!=date_presc`j'[`i'])
}
}

weights not allowed


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