topic Re: Using %let statements as filename shortcuts in loop in SAS Programming

Using %let statements as filename shortcuts in loop

JenniferBernard — Wed, 24 Feb 2021 21:49:07 GMT

Hello all. I have a question about using %let statements as a shortcut for full filenames. Could someone tell me why this works:

%let file2005 = "/datapath/2005/filename2005";

But this doesn't:

%macro yrloop(firstyr,lastyr);

%do yr=&firstyr. %to &lastyr;

%let file&yr.= "/datapath/&yr./filename&yr.";

%end; %mend;

%yrloop(2005,2005);

How do I get the &yr. macro to resolve in the let statement? Thanks!

Re: Using %let statements as filename shortcuts in loop

Reeza — Wed, 24 Feb 2021 21:56:56 GMT

It works fine....what do you mean it doesn't work? I suspect you're running into a scope issue, the macro variable only exists within that macro and doesn't exist outside unless you create it as a global macro variable.

%macro yrloop(firstyr,lastyr);

%do yr=&firstyr. %to &lastyr;
%global file&yr.;

%let file&yr.= "/datapath/&yr./filename&yr.";

%put &&file&yr.;

%end; 

%mend;

%yrloop(2000,2005);

%put &file2000.;

%put &file2005.;

@JenniferBernard wrote:

Hello all. I have a question about using %let statements as a shortcut for full filenames. Could someone tell me why this works:

%let file2005 = "/datapath/2005/filename2005";

But this doesn't:

%macro yrloop(firstyr,lastyr);

%do yr=&firstyr. %to &lastyr;

%let file&yr.= "/datapath/&yr./filename&yr.";

%end; %mend;

%yrloop(2005,2005);

How do I get the &yr. macro to resolve in the let statement? Thanks!

Re: Using %let statements as filename shortcuts in loop

mklangley — Wed, 24 Feb 2021 21:57:44 GMT

Try defining the macro variable as global inside the macro:

%macro yrloop(firstyr,lastyr);
    %do yr=&firstyr. %to &lastyr;
        %global file&yr.;
        %let file&yr.= "/datapath/&yr./filename&yr.";
    %end; 
%mend;
%yrloop(2005,2005);

%put &=file2005;

Re: Using %let statements as filename shortcuts in loop

JenniferBernard — Thu, 25 Feb 2021 13:26:29 GMT

Thank you so much! This was the issue exactly. I needed to call them outside the macro.