topic Re: macro loop %if %then not evaluating correctly in SAS Programming

macro loop %if %then not evaluating correctly

mhodge20 — Tue, 06 Feb 2018 22:14:20 GMT

This is within a macro function.

Example termdate = 01/01/2007

%do II = 0 %to 11;
			%let x = %sysfunc(intnx(month,&termdate.,&ii,B),Date9.);
			%let t = %str(%')&x.%str(%')d;
			%put &t.;
			%put &ii;


					%if %sysevalf(&t.) ge '01FEB2018'd %then %do;

the %put &t. produces:

'01JAN2007'd

but then when I use it in the %if statement below

it evaluates to TRUE when using Mlogic option.

It should be False.

This is how it should look when the macro variable has been resolved.

%if '01JAN2007'd ge '01FEB2018'd %then %do;

Should be false but it comes out true.

Re: macro loop %if %then not evaluating correctly

novinosrin — Tue, 06 Feb 2018 22:17:29 GMT

try :

%if %sysevalf(&t. ge '01FEB2018'd) %then %do;

Re: macro loop %if %then not evaluating correctly

Astounding — Tue, 06 Feb 2018 22:18:47 GMT

Macro language doesn't understand dates. It understands character strings. If you want to force it to make the "right" comparison, you can do it with:

%if %sysevalf(&t.) ge %sysevalf('01FEB2018'd) %then %do;

Re: macro loop %if %then not evaluating correctly

Reeza — Tue, 06 Feb 2018 22:25:19 GMT

Is that all your code? If so, you should use a data step and data step loop, not a macro loop.

@mhodge20 wrote:

This is within a macro function.

Example termdate = 01/01/2007
%do II = 0 %to 11;
			%let x = %sysfunc(intnx(month,&termdate.,&ii,B),Date9.);
			%let t = %str(%')&x.%str(%')d;
			%put &t.;
			%put &ii;


					%if %sysevalf(&t.) ge '01FEB2018'd %then %do;
the %put &t. produces:

'01JAN2007'd

but then when I use it in the %if statement below

it evaluates to TRUE when using Mlogic option.

It should be False.

This is how it should look when the macro variable has been resolved.
%if '01JAN2007'd ge '01FEB2018'd %then %do;
Should be false but it comes out true.

Re: macro loop %if %then not evaluating correctly

ballardw — Tue, 06 Feb 2018 22:26:14 GMT

@mhodge20 wrote:

This is within a macro function.

Example termdate = 01/01/2007

the %put &t. produces:

'01JAN2007'd

but then when I use it in the %if statement below

it evaluates to TRUE when using Mlogic option.

It should be False.

This is how it should look when the macro variable has been resolved.
%if '01JAN2007'd ge '01FEB2018'd %then %do;
Should be false but it comes out true.

No it shouldn't. Strings are compared one character at a time until a difference (if any) is found: 0=0, 1=1 but J>F.

for added fun check on this

%if '01JAN2007'd ge '01feb2018'd %then %do;

Re: macro loop %if %then not evaluating correctly

Tom — Wed, 07 Feb 2018 14:56:41 GMT

The condition in a %IF is normally evaluated using the %EVAL() macro function. That function does not handle floating point numbers or literals. So you need to generate your own test using the %SYSEVALF() macro function instead if you are comparing date literals.

Also you need to convert your date like string into a date value, either an actual number of days or a date literal, before you can compare dates.

%let datenumber = %sysfunc(intnx(month,&termdate.,&ii,B));
%let dateliteral = "%sysfunc(intnx(month,&termdate.,&ii,B),Date9.)"d;
%if %sysevalf(&datenumber. ge '01FEB2018'd) %then %do;
%if %sysevalf(&dateliteral. ge '01FEB2018'd) %then %do;