This isn't a reshape-like problem in my book, as no overall change to data structure or shape is needed: you just want new identifier variables.
In the example -id- was just equivalent to observation number. In that circumstance
gen ID_1 = ceil(_n/3)
is an alternative, as are
egen id__1 = seq(), block(3)
egen id__2 = seq(), to(3)
The first is easy to think about: you are just rounding up 1/3, 2/3, 3/3, 4/3, ... to the next integer.
The second two are just wrappers for trickery with -mod()- and -int()-. (I think -egen, seq()- predates -ceil()-.)
Nick
[email protected]
Austin Nichols
Pancho Villa <[email protected]> :
clear
input id value
1 15
2 14
3 22
4 31
5 12
6 10
end
g id_1=(id-mod(id-1,3)-1)/3+1
g id_2=mod(id-1,3)+1
l
On Thu, Jun 4, 2009 at 2:15 PM, Pancho Villa <[email protected]> wrote:
> I have my data in this kind of form:
>
> id value
> 1 15
> 2 14
> 3 22
> 4 31
> 5 12
> 6 10
>
> id_1 id_2 value
> 1 1 15
> 1 2 14
> 1 3 22
> 2 1 31
> 2 2 12
> 2 3 10
>
> In other words, my data is stacked and would like to un-stack it. (I
> can do reshape, I think. But this seems like a necessary first step.)
>
> Now, in my example, my id goes from 1 to 6, while I'd like id_1 to go
> from 1 to 2 and id_2 from 1 to 3. In reality, my id goes from 1 to
> 5084280, while I want id_1 to go from 1 to 2088 and id_2 from 1 to
> 2435. (If you check, 2088 x 2435 = 5084280.)
>
> I'll really appreciate if you can share code addressing a very similar
> problem so I can just paste it in my do file and tweak a few things.
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