topic Re: _N_ not working in SAS Procedures

_N_ not working

R_A_G_ — Fri, 08 Apr 2011 16:20:31 GMT

Hello,

I've got another problem, I am using _N_ to have a count for my observations but for some reason it does not give me the correct count

Thanks
R.A.G
my Code:
data class (rename=(skills1-skills&num_skills=attributes1-attributes&num_skills));
set all_skills1;
array skills{&num_skills} skills1-skills&num_skills;
num=%eval(&num_skills);
if _type_=(2**num)-1 and sum(of skills1-skills&num_skills) ne .;

/*Lambda Intercept*/
num=1;
class=_n_;/****************************HOW???*************/
/*Lambda Main Effect*/
drop num _type_ _freq_ num;

run;

Re: _N_ not working

sbb — Fri, 08 Apr 2011 17:42:08 GMT

What is the value you are getting? Have you included this statement to verify with accuracy:

PUTLOG _ALL_;

Scott Barry
SBBWorks, Inc.

Re: _N_ not working

R_A_G_ — Fri, 08 Apr 2011 17:56:17 GMT

the values I am getting starts from 66 and ends with 81, I have 4 variables with 16 observations.
Thanks

Re: _N_ not working

Tim_SAS — Fri, 08 Apr 2011 18:19:05 GMT

_N_ counts the number of times the DATA step has iterated. It is not a count of observations.

See the doc about Automatic Variables.

Re: _N_ not working

NickR — Fri, 08 Apr 2011 18:19:47 GMT

_N_ is the count of observation read from the input dataset and not the observation written to output dataset.

In your case, you are subsetting the data and then assigning the value of _N_ to class variable. How about replacing the statement "class=_n_;" with "class+1;"

Re: _N_ not working

R_A_G_ — Fri, 08 Apr 2011 18:31:11 GMT

thanks, that worked, but why?
thanks again
R.A.G

Re: _N_ not working

Ksharp — Mon, 11 Apr 2011 03:39:05 GMT

Because you have "if _type_=(2**num)-1 and sum(of skills1-skills&num_skills) ne .; ".

"if _type_=(2**num)-1 and sum(of skills1-skills&num_skills) ne .; " is actually ""if _type_=(2**num)-1 and sum(of skills1-skills&num_skills) ne . then output;"

That means only obs 66 - 81 suited this condition (i.e. _N_ = 66 - 81),only obs 66 - 81 will output dataset.

Ksharp