Re: st: adding or counting values as an array

[Nick Cox <njcoxstata@gmail.com>]

gen ones = 0
gen zeros = 0

qui foreach v of var y2006q_1-y2010q_3 {
     replace ones = ones + (`v' == 1)
     replace zeros = zeros + (`v'' == 0)
}

If there are no missings,

egen ones = rowtotal(y2006q_1-y2010q_3)
gen zeros = <number of variables> - ones

The yearwise calculation is a variation on the same theme.

See also SJ-9-1  pr0046  . . . . . . . . . . . . . . . . . . .
Speaking Stata: Rowwise
        (help rowsort, rowranks if installed) . . . . . . . . . . .  N. J. Cox
        Q1/09   SJ 9(1):137--157
        shows how to exploit functions, egen functions, and Mata
        for working rowwise; rowsort and rowranks are introduced

For most Stata analyses, -reshape long- is advised.

On Thu, Oct 6, 2011 at 6:49 AM, Daniel Exeter <d.exeter@auckland.ac.nz> wrote:

> In Stata 11 (win7, 64bit),  I have a dataset with quarterly observations of events from 2006 to 2011.
> Each field is named y2006_q1, y2006_q2 .. y2011_2
>
> The data is dichotomous (0/1) and I want to know:
> -for the entire period (q1 2006 to q3 2011)  and separately for each year
> -       how many quarters each event was observed
> -       how many quarters each event was not observed
>
>
> is there an easy way to code something that would do this:
>
> gen included = sum (yr20*) if yr20* ==1
> gen excluded = count (yr20*) if  yr20* ==0
>
> and
>
> gen inc06 = sum (yr2006*) if yr2006 ==1
> gen exc06 = count(yr2006*) if yr2006 ==0
>

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