Hello, I am trying to sum across columns only the 1s.

I have tried
egen pri_sum=rowtotal(pri_q1-pri_q7) if (pri_*) < 2

and

egen pri_sum=rowtotal(pri_q1-pri_q7) if pri_* < 2


I think that "if" just does not work for conditioning on row total. Is there another option?


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Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input byte(id pri_q1 pri_q2 pri_q3 pri_q4 pri_q5 pri_q6 pri_q7)
 1 1 1 1 1 2 2 1
 2 1 1 1 1 1 2 1
 3 2 2 2 2 1 2 2
 4 1 1 1 1 1 3 1
 5 1 2 2 1 2 2 2
 6 1 1 1 2 2 1 2
 7 1 1 1 1 2 1 2
 8 1 1 1 1 3 2 2
 9 1 2 1 3 3 1 1
10 1 1 1 1 1 1 1
11 1 1 1 1 1 1 1
12 1 1 1 1 1 1 2
13 1 1 1 1 1 1 1
14 1 2 2 2 1 2 2
15 1 1 1 1 1 1 1
16 1 2 2 1 3 1 1
17 1 2 2 2 1 1 2
18 1 2 2 2 1 1 1
19 1 2 2 2 1 2 2
20 1 1 1 1 1 2 2
21 1 1 1 3 1 2 1
22 1 2 2 1 1 1 2
23 1 1 1 1 2 2 2
24 1 1 1 1 1 1 2
25 1 1 1 1 2 2 2
26 1 1 2 1 2 2 2
27 1 1 1 3 3 1 3
28 1 2 2 1 1 2 1
29 1 1 1 3 1 1 2
30 2 2 2 2 2 2 2
31 1 1 1 1 1 2 1
32 1 1 1 1 1 1 1
33 1 2 1 1 2 2 2
34 1 2 2 1 2 2 2
35 1 1 1 2 1 2 2
36 1 1 2 2 1 2 2
37 1 3 1 2 2 2 2
38 1 1 1 1 1 1 2
39 1 1 1 1 3 1 2
40 1 1 1 1 2 1 2
end