SAS Macro to export to csv - macros

Question

I'm trying to use code from here and not sure how to adapt it correctly.
https://communities.sas.com/thread/33654?start=0&tstart=0
I'm trying to export 51 SAS datasets to CSV files so that I can import them into R. Here's the macro code I have (that's not working):
libname g 'C:\mylibrary';
%macro export(libname, numvars= &numvars.);
%do i= 1 %to &numvars.;
proc export data=&libname.StateZip&i
DBMS=CSV REPLACE
outfile= "&libname.StateZip&i.csv";
run;
%end;
%mend;
%export(&g, numvars= 51);
Here is the error message I'm getting:
NOTE: Writing TAGSETS.SASREPORT12(EGSR) Body file: EGSR
13
14 GOPTIONS ACCESSIBLE;
ERROR: Invalid macro name (. It should be a valid SAS identifier no longer than 32 characters.
ERROR: A dummy macro will be compiled.
15 %macro export(libname, numvars= &numvars.);
16 %do i= 1 %to &numvars.;
17 proc export data=&libname.StateZip&i
18 DBMS=CSV REPLACE
19 outfile= '&libname.StateZip&i.csv';
20 run;
21 %end;
22 %mend;
23
24 %export(g, numvars= 51);
24 +(libname, numvars= &numvars.);
_
10
ERROR 10-205: Expecting the name of the procedure to be executed.
24 +(libname, numvars= &numvars.);
_
180
ERROR 180-322: Statement is not valid or it is used out of proper order.
2 The SAS System 11:38 Wednesday, September 5, 2012
180: LINE and COLUMN cannot be determined.
NOTE: NOSPOOL is on. Rerunning with OPTION SPOOL may allow recovery of the LINE and COLUMN where the
error has occurred.
Any help you can provide would be appreciated.

Answer 1

You have a recursive reference to &numvars, which is a problem in and of itself, but not a critical one - just means that the default value will be null, not the value you intend it to be. Otherwise your code works fine for me. I would guess you have something else going wrong just before the %macro definition; the error you post makes it look like you have a token that's incorrectly resolving, so instead of
%macro export(
you have
%macro (
Anyway, this is what works for me:
%let g=c:\temp;
libname g "&g.";
%macro export(libname, numvars=);
%do i= 1 %to &numvars.;
proc export data=sashelp.class
DBMS=CSV REPLACE
outfile= "&g.\StateZip&i.csv";
run;
%end;
%mend;
%export(&g, numvars= 51);
The things I changed:
* You need a %let g= to go along with your libname. You don't have that defined, but presumably you do elsewhere.
* Sashelp.class instead of using your library as I don't have those datasets.
The better answer, though, is probably to do it like this, using FILEVAR option and writing them out yourself. Even if you have a ton of variables, you can either programmatically determine the put statement, or just do one proc export and copy from the log. This avoids all of the macro stuff, and avoids you having to make 51 different datasets. Just make one, with an indicator variable. Pretty much no matter what you're doing, this will be faster (using BY group processing with PROCs, etc.) and less error-prone than having a bunch of different datasets and making up for it with macros.
data have_51;
set sashelp.class;
do _n = 1 to 51;
output;
end;
run;
*I assume you have have_51 already;
data want;
set have_51;
filename=cats("&g.\StateZip",_n,".csv");
run;
proc sort data=want;
by filename;
run;
data _null_;
set want;
file a filevar=filename dlm=',' lrecl=500;
put
name $
age
height
weight
;
run;