topic Re: return first digit of a numeric variable in SAS Programming

return first digit of a numeric variable

CharlesR — Mon, 18 Apr 2011 03:27:45 GMT

Ok, I've googled this and searched the sas website and i'm just not finding the answer to this most simple of questions:

I need to return the first digit of a numeric variable into a new variable. Can someone please give me the data step i need or the command in proc sql?

Thanks!

Re: return first digit of a numeric variable

Ksharp — Mon, 18 Apr 2011 10:18:39 GMT

[pre]
data digit;
input id;
datalines;
107
204
508
359
;
run;
proc sql;
create table want as
select *,left(put(id,best20.)) length=1 as firstdigit
from digit;
quit;
[/pre]

Ksharp

Re: return first digit of a numeric variable

AmarMundankar — Mon, 18 Apr 2011 11:43:38 GMT

Hi CharlesR,
You can also make use of substr() funtion.

data have;
input id;
datalines;
107
204
508
359
;
run;
data want;
set have;
length id2 $1;
id2 = substr(put(id,best12.),1,1);
put id2=;
run;

Thanks,
Amar Mundankar.

Re: return first digit of a numeric variable

DBailey — Mon, 18 Apr 2011 12:28:14 GMT

you would need to use the left function as well:

id2=substr(left(put(id,best12.)),1,1);

Re: return first digit of a numeric variable

CharlesR — Mon, 18 Apr 2011 17:37:06 GMT

Thanks to everyone for the responses! Really appreciate all the help!!

Re: return first digit of a numeric variable

CharlesR — Mon, 18 Apr 2011 19:31:59 GMT

Hey KSharp,
Is there a way to use this to create a numeric variable instead of a character one? or do i just need to convert it back to a numeric after i'm done?

Thanks,
cr

Re: return first digit of a numeric variable

ballardw — Mon, 18 Apr 2011 19:54:18 GMT

> Hey KSharp,
> Is there a way to use this to create a numeric
> variable instead of a character one? or do i just
> need to convert it back to a numeric after i'm done?
>
> Thanks,
> cr

Not the best programming practice but if you leave off the length declaration the target variable will default to numeric and you'll get a numeric result and warnings in the log about conversion from string to numeric.

Re: return first digit of a numeric variable

chang_y_chung_hotmail_com — Mon, 18 Apr 2011 20:31:03 GMT

See an excellent solution without type conversions at sas-l:
http://www.listserv.uga.edu/cgi-bin/wa?A2=ind0001B&L=sas-l&D=0&P=30671

Re: return first digit of a numeric variable

Ksharp — Tue, 19 Apr 2011 00:53:47 GMT

Yes.You need to convert it back to a numeric after it.

Ksharp

Re: return first digit of a numeric variable

Ksharp — Tue, 19 Apr 2011 01:15:02 GMT

That is pure mathematics way.I like it.

Re: return first digit of a numeric variable

david2010 — Tue, 19 Apr 2011 01:27:19 GMT

This is a format problem. What you want is the first significant digit of the number.

Check David Chapman's NESUG or SUGI paper on user define formats and proc report. He shows how to create a format to show the first two significant digits. Just modify that to show the first significant digit.