the two digit of a number in the data

[Faisal Abdullah]

Hello every one,
I am trying to use the two digit from the industry classification code to generate industry dummies that are based on the first two digit of the database classification. for example,

sic_2
5080
5080
5080
5080
5080
3743
3661
3661
3661
3661
3661
3211
2834

I would like to generate a new variable that takes the first two digit from the written above sic_2 code. like 50 50 50 37 36 etc.
I tried several times in excel but the merge did not work for me

many thanks and regards for your support
Faisal

[Friedrich Huebler]

I assume that sic_2 is a string variable that can contain leading zeros.

gen group = substr(sic_2,1,2)

[Brendan Cox]

Note that to use sic_2 to generate industry dummy variables, you may want to -encode- the string variable and then use factor variable notation (see -help fvvarlist-).

[Rich Goldstein]

no reason to go through two steps; just edit the code in #2:

 
 gen group = real(substr(sic_2,1,2))

and then use factor variable notation as per #3

[Brendan Cox]

no reason to go through two steps; just edit the code in #2:

gen group = real(substr(sic_2,1,2))

and then use factor variable notation as per #3

Quite right. The only reason to use string variables and -encode- is because it would be more normal to see an SIC code of, e.g., "01" rather than "1" in the data and output.

[William Lisowski]

Applying an appropriate format will display a SIC code stored as a numeric variable with leading zeroes as appropriate.

. set obs 1
obs was 0, now 1

. gen group = real(substr("0123",1,2))

. format group %02.0f

. list

     +-------+
     | group |
     |-------|
  1. |    01 |
     +-------+

[Brendan Cox]

Applying an appropriate format will display a SIC code stored as a numeric variable with leading zeroes as appropriate.

. set obs 1
obs was 0, now 1

. gen group = real(substr("0123",1,2))

. format group %02.0f

. list

+-------+
| group |
|-------|
1. | 01 |
+-------+

Ah, good point. Hadn't thought to do that.

[Faisal Abdullah]

unfortunately, it did not work for me.
what I need is to keep only the the first two number of the sic_variable
for example if the value of sic_2 is 5050 , i only want to keep the first to digits so it becomes 50

I really appreciate your cooperation

[Faisal Abdullah]

the following table shows the new variable I made in excel

year	cusip_en	sic_2	two_digit of sic_2
2006	361105	5080	50
2007	361105	5080	50
2008	361105	5080	50
2009	361105	5080	50
2010	361105	5080	50
2006	00081T108	2780	27
2007	00081T108	2780	27
2008	00081T108	2780	27
2009	00081T108	2780	27
2010	00081T108	2780	27
2004	886309	3661	36
2005	886309	3661	36
2007	886309	3661	36
2008	886309	3661	36
2010	886309	3661	36
1992	915306	7380	73
1993	915306	7380	73

[Nick Cox]

Please see FAQ Advice esp. #12: "did not work" is not an informative report. But we can try guesswork. If your variable is numeric then

gen mysic_2  = floor(sic_2/100)

is one technique.

[Friedrich Huebler]

unfortunately, it did not work for me.

From the FAQ:

Say exactly what you typed and exactly what Stata typed (or did) in response. N.B. exactly!

[...]

Never say just that something “doesn't work” or “didn't work”, but explain precisely in what sense you didn't get what you wanted.

Several list members proposed solutions that do what you asked for. Which commands did you try and what was the result?