Keeping only two first digits of a numeric variable

[Iuliia Svetetskaia]

Hello!

I am currently working with a pretty big dataset, and I am trying to change one variable (which is a regional indicator) so it would contain only first digit / first two digits.

The thing is that this variable has different lengths - it is either 10 digits (ex. 7412000000) or 11 digits (ex. 45333000000) long, and so in the case when it is 10 digits, I want to keep only the first digit, and when it is 11 digits, I want to keep the first two digits.

I am also not sure whether I should replace the values of the original variable, or try to generate a new one.

Thank you for your suggestions in advance!

[Nick Cox]

Is your identifier really numeric, or perhaps string? The solution will be different.

clear
input double nid
7412000000
45333000000
end

format nid %12.0f
gen sid = strofreal(nid, "%12.0f")

gen wanted_s = cond(length(sid) == 11, substr(sid, 1, 2), substr(sid, 1,1))

gen wanted_n = floor(nid/1e9)

list

     +-------------------------------------------------+
     |         nid           sid   wanted_s   wanted_n |
     |-------------------------------------------------|
  1. |  7412000000    7412000000          7          7 |
  2. | 45333000000   45333000000         45         45 |
     +-------------------------------------------------+

[Iuliia Svetetskaia]

Is your identifier really numeric, or perhaps string? The solution will be different.

clear
input double nid
7412000000
45333000000
end

format nid %12.0f
gen sid = strofreal(nid, "%12.0f")

gen wanted_s = cond(length(sid) == 11, substr(sid, 1, 2), substr(sid, 1,1))

gen wanted_n = floor(nid/1e9)

list

+-------------------------------------------------+
| nid sid wanted_s wanted_n |
|-------------------------------------------------|
1. | 7412000000 7412000000 7 7 |
2. | 45333000000 45333000000 45 45 |
+-------------------------------------------------+

Hello, Nick!

It is numeric.

I've run your code, it worked perfectly.

Thank you so much!