calculate all values without repetition

[Fariba Ghoutaslou]

How do I get one value when I want to calculate all values without repetition?

[Maarten Buis]

That depends on what you want that value to be: the sum, the mean, do you want to drop duplicate rows?

[Fariba Ghoutaslou]

yes, I want just one of the value and dropp the duplicate.

[Maarten Buis]

bysort id_notice_can year value2 : keep if _n == 1

[Fariba Ghoutaslou]

thank you so much

[Fariba Ghoutaslou]

it seems doesn't work. this syntax, delete the observations. I want to keep them but in caculation use one of the values.

[Maarten Buis]

 bysort id_notice_can year value2 : gen byte mark = _n == 1
some_other_command_doing_some_unspecified_calculation if mark == 1

[Fariba Ghoutaslou]

thank you