topic Re: How to recursively get the number of observation, looping through data sets in SAS Programming

How to recursively get the number of observation, looping through data sets

tommymene86 — Mon, 09 Jul 2018 08:13:15 GMT

Hi everyone,

what I'm trying to achieve is loop through some tables-data sets, getting the number of observation of each table.

So, suppose I’ve the following situation:

data tabl1;
	input name $ age;
	datalines;
	TOM 40
	TIM 50
	JIM 30
	JOHN 20
	;
run;
data tabl2;
	input surname $ city $;
	datalines;
	JOHNSON LONDON
	THOMPSON ROME
	STONE TORONTO
	;
run;

Reading the various support forums, I’ve come across with this solution:

1. create a data set with the tables I want:

data tabs;
	set sashelp.vstable;
	where libname='WORK' and upcase(memname) contains 'TABL';
	tab_name=memname;
	keep tab_name;
run;

2. create an array with to loop in and get the number of observations from the descriptive part of the data set:

data _null_;
	set work.tabs nobs=n;
	call symput ('num_tab',n);
	call symput ('tab',"");	

run;

data test;
	array tables[&num_tab] $32767. _temporary_;
	if _N_=1 then do j=1 to number_of_obs;
		set work.tabs nobs=number_of_obs;
		tables[j]=tab_name;
	end;
	else go to end_p;
	do i=1 to dim(tables);
		call symputx (cats('tab'),tables[i]);
		if 0 then set work.&tab nobs=nob;
		n=nob;
		output;
	end;
	keep tab_name n;
end_p: run;

Unfortunately I'm not getting the number of observation for each data set.

What I'm trying to achieve s this:

tab_name	n
TABL1		4
TABL2		3

What I'm doing wrong? Is this the best way to do it?

Thanks for the help!

Re: How to recursively get the number of observation, looping through data sets

Oligolas — Mon, 09 Jul 2018 11:52:31 GMT

Hi you can directly extract the number of observations from the SAS metadata. There is no need to Loop through them.

DATA _NULL_;
   set sashelp.vtable(keep= libname memname nobs);
   where libname eq 'SASHELP' and memname eq 'CLASS';
   put 'W' 'ARNING: number of obs in ' libname= memname 'is ' nobs;
RUN;

Re: How to recursively get the number of observation, looping through data sets

Oligolas — Mon, 09 Jul 2018 11:59:54 GMT

in your case:

DATA _NULL_;
   set sashelp.vtable(keep= libname memname nobs);
   where libname eq 'WORK' and memname in ('TABL1','TABL2');
   put 'W' 'ARNING: number of obs in ' libname memname 'is ' nobs;
RUN;

Re: How to recursively get the number of observation, looping through data sets

ballardw — Mon, 09 Jul 2018 15:42:09 GMT

@Oligolas wrote:

in your case:

DATA _NULL_;
   set sashelp.vtable(keep= libname memname nobs);
   where libname eq 'WORK' and memname in ('TABL1','TABL2');
   put 'W' 'ARNING: number of obs in ' libname memname 'is ' nobs;
RUN;

@Oligolas

May I ask why you use

put 'W' 'ARNING: number of obs in '

instead of

put 'WARNING: number of obs in '

Re: How to recursively get the number of observation, looping through data sets

PaigeMiller — Mon, 09 Jul 2018 17:01:29 GMT

So if you are searching a SASLOG for WARNING, the line of code that begins put 'W' isn't found by the search.

Similarly, you can do this for user generated ERROR statements that appear in the SASLOG.

Re: How to recursively get the number of observation, looping through data sets

Oligolas — Tue, 10 Jul 2018 06:47:41 GMT

oh.. just routine. By writing it this way I bypass a program that searches for warnings, errors and special notes in the log and I directly get to the section where the notification is raised when I search by myself