Dear Nick,
Thank you very much for the quick response. Regarding your comment about
the group variable, the 'group' number varies and 'states' are sometimes
repeated across groups, so I will need the loop to run across groups.
I am a newbie to Stata programming (sadly, I took data out to Matlab to
program in the past), but can I simply add commands like the following
to the program you kindly wrote for me?
gen sumlength = .
levelsof state, local(S)
levelsof group, local(G)
qui foreach g of local G {
qui foreach s of local S {
...
}
}
Thank you again. I will grateful (again) for a "reply all" rather than
"reply".
Mushfiq
-----Original Message-----
From: Nick Cox [mailto:[email protected]]
Sent: Friday, December 09, 2005 6:11 AM
To: [email protected]
Cc: A. Mobarak
Subject: RE: summation
gen sumlength = .
levelsof state, local(S)
qui foreach s of local S {
su min if state == `s', meanonly
local min = r(min)
su max if state == `s', meanonly
local max = r(max)
su length if inrange(n, `min', `max'), meanonly
replace sumlength = r(sum) if state == `s'
}
Whether the variable -group- complicates
your problem is not clear.
Nick
[email protected]
A. Mushfiq Mobarak, Assistant Professor of Economics
> I post a part of my dataset below. I would like to sum the variable
> "length" from n=min to n=max for each state, where n, min and
> max are 3
> different variables. I'm using Stata8SE.
>
> So, for example, for state=1, the answer I'm looking for would be:
>
> summation (n going from 2 to 20) of "length', which equals
> 10+20+30+....+190 = 1900
>
> For state=3, the answer would be summation (n going from 6 to 16) of
> length = 50+60+.+150 = 1100
>
> For state=2, I would just get "." (missing)
>
> This is a very large dataset, which is why I need to automate the
> summing procedure. I apologize in advance if the answer is obvious. I
> will be grateful for any help or suggestions. I subscribe to
> the digest
> version, so copying the response to [email protected]
> (hitting "reply
> all" rather than "reply" may also work) will help me get your response
> quicker.
>
> group n min max state length
> 3 2 2 20 1 10
> 3 3 . . 2 20
> 3 4 2 20 1 30
> 3 5 2 20 1 40
> 3 6 6 16 3 50
> 3 7 2 20 1 60
> 3 8 6 16 3 70
> 3 9 2 20 1 80
> 3 10 6 16 3 90
> 3 11 2 20 1 100
> 3 12 6 16 3 110
> 3 13 2 20 1 120
> 3 14 6 16 3 130
> 3 15 2 20 1 140
> 3 16 6 16 3 150
> 3 17 17 25 4 160
> 3 18 2 20 1 170
> 3 19 17 25 4 180
> 3 20 2 20 1 190
> 3 21 17 25 4 200
> 3 22 22 28 5 210
> 3 23 17 25 6 220
> 3 24 22 28 5 230
> 3 25 17 25 6 240
> 3 26 22 28 5 250
> 3 27 . . 7 260
> 3 28 22 28 5 270
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