topic macro loop error in SAS Programming

macro loop error

Kethy — Sun, 09 Oct 2011 13:28:36 GMT

i have this below code working fine for positive parameters but throws an error for negative values.

could anyone help!

%macro doit(m,n);

%do i=&m %to &n;

%global st&i ;

data _null_;

st=intnx('month',today(),&i,'b');

call symput("st&i",put(st,date9.));

%end;

%mend;

%doit(-2,-1)

%put &st-1 &st-2;

macro loop error

Tom — Sun, 09 Oct 2011 14:03:44 GMT

It helps to post the error messages:

ERROR: Invalid symbolic variable name -.

ERROR: Invalid symbolic variable name 2.

You cannot define a macro variable named ST-1 or ST-2.

macro loop error

Kethy — Sun, 09 Oct 2011 15:19:49 GMT

how can i define then for negative values? any suggestion!

macro loop error

art297 — Sun, 09 Oct 2011 15:25:45 GMT

How do you want to use it? You count always just assign a counter. The values can be negative but, like Tom said, the negatives can't be included in the macro variable name.

macro loop error

Kethy — Sun, 09 Oct 2011 15:38:32 GMT

i want to save the past month start date values into macro variables.how can this be done in above case?

macro loop error

art297 — Sun, 09 Oct 2011 15:49:28 GMT

Not sure if I fully understand, but do you want something like:

%macro doit(m,n);

%do i=&m %to &n;

%global last&i;

data _null_;

st=intnx('month',today(),%eval(0-&i),'b');

call symput("last"||strip(&i),put(st,date9.));

run;

%end;

%mend;

%doit(1,2)

%put &last1 &last2;

macro loop error

Kethy — Sun, 09 Oct 2011 16:22:44 GMT

Right now im creating the macro variable "st" based on the i values as st&i,

when %doit(1,2) is called st1 and st2 will be the macro variables being created(no issues here)

when %doit(-2,-1) is called as pointed out by you and Tom negatives cannot be included in macro variables, so in that case is there any better way where i can create a macro variable(instead of st&i) which would work fine in both the cases [ %doit(1,2) and %doit(-2,-1)]

macro loop error

art297 — Sun, 09 Oct 2011 16:28:36 GMT

What do you want the macro variables to be called?

macro loop error

Kethy — Sun, 09 Oct 2011 16:43:14 GMT

I mean when the macro %doit() is called irrespective of the positive or negative values being passed as parameters, it should create a macro variable which will hold the start of the month date corresponding to its values passed .

macro loop error

art297 — Sun, 09 Oct 2011 17:53:25 GMT

Would something like the following suffice?

%macro doit(m,n);

%do i=&m %to &n;

data _null_;

st=intnx('month',today(),&i,'b');

%if &i lt 0 %then %do;

%global before%eval(0-&i);

call symput("before"||strip(%eval(0-&i)),put(st,date9.));

%end;

%else %do;

%global after&i;

call symput("after"||strip(&i),put(st,date9.));

%end;

run;

%end;

%mend;

%doit(-2,-1)

%put &before1 &before2;

%doit(1,2)

%put &after1 &after2;

macro loop error

Kethy — Mon, 10 Oct 2011 00:10:25 GMT

Great! Thanks art.