topic Re: How to assign value to macro variable from another variable? in SAS Programming

How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 09:34:36 GMT

I'm doing a batch work with SAS programming, where I have a series of var to assign.

with vars = va|vb|vc

, in a do loop

, get var = vars[i],

, get temp local var_i

, let &var(actually va/vb/vc) = &&var_&i;

But the last step isn't working, I guess SAS won't let variable resolved at [LET VAR_NM = ] syntax..

So, Is there a function I may use to copy value from variable to variable?

Or any better way to finish this batch work?

Thanks very much, Say hi to the community from Guangzhou, China.

Re: How to assign value to macro variable from another variable?

PaigeMiller — Tue, 14 Sep 2021 10:04:53 GMT

I'm not 100% sure I understand what you are asking here ... but maybe this is it ...

%macro dothis;
%let vars=va vb vc;
%do i=1 %to %sysfunc(countw(&vars));
     %let var&i=%scan(&vars,&i,%str( ));
%end;
%put &var1 &var2 &var3;
%mend;
%dothis

Re: How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 10:22:38 GMT

Thanks for your reply, Sir. This is partial of my work though, once you get var1 which is the name of my wanted global vars, va respectively. I need to convey a local value from another temp var. I did [%let &&var&i = &var_temp] in your context, hoping this would make va = &var_temp globally, but It failed...

Thank you for your patience again, Sir.

Re: How to assign value to macro variable from another variable?

PaigeMiller — Tue, 14 Sep 2021 10:25:59 GMT

@kimmygzc wrote:

Thanks for your reply, Sir. This is partial of my work though, once you get var1 which is the name of my wanted global vars, va respectively. I need to convey a local value from another temp var. I did [%let &&var&i = &var_temp] in your context, hoping this would make va = &var_temp globally, but It failed...

Thank you for your patience again, Sir.

I guess then I don't understand what you are trying to do, and it would help if you can be more specific and give concrete examples of "I need to convey a local value from another temp var". I'm not asking for code, I'm asking what the macro variable values are how you want to move them around.

Re: How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 10:37:37 GMT

Sure, Say:

%let vars = va|vb|vc

%macro batch_assign;
%do i = 1 to %sysfunc(countw(&vars, %str(|)));
  var = %scan(&vars, &i, %str(|));
  %get_value(ind = i, tmep = t); /*In this func, t is assigned with 'Hi,1'/'Hi,2'/'Hi,3'*/
  %let &&var = &t; /*var should be twice resolved, which I think SAS would avoid.*/
%mend;
%batch_assign;

What I want is, globally, I have va = 'Hi,1', vb = 'Hi,2', vc = 'Hi,3'; Which is actually, batch assignment from function get_value.

Re: How to assign value to macro variable from another variable?

PaigeMiller — Tue, 14 Sep 2021 10:41:29 GMT

Can't read your code, please reformat it.

Re: How to assign value to macro variable from another variable?

Kurt_Bremser — Tue, 14 Sep 2021 10:42:49 GMT

Please show what you "have", and then what you "want" out of it.

Syntactically erroneous one-line(!!!) code doesn't tell us anything.

Re: How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 10:47:04 GMT

Sorry, Sir, Im new to this editor...

%let vars = va|vb|vc;
%macro batch_assign;
  %do i = 1 to %sysfunc(countw(&vars, %str(|)));  
  var = %scan(&vars, &i, %str(|));  
  %get_value(ind = i, tmep = t); /*In this func, t is assigned with 'Hi,1'/'Hi,2'/'Hi,3'*/  
  %let &var = &t; 
/*var should be resolved and refered to va/vb/vc
, which I think SAS would avoid.*/
%mend;
%batch_assign;

In case if it's not formatted in the block:

%let vars = va|vb|vc;

%macro batch_assign;
%do i = 1 to %sysfunc(countw(&vars, %str(|)));
var = %scan(&vars, &i, %str(|));
%get_value(ind = i, tmep = t); /*In this func, t is assigned with 'Hi,1'/'Hi,2'/'Hi,3'*/
%let &var = &t;
/*var should be resolved and refered to va/vb/vc
, which I think SAS would avoid.*/
%mend;
%batch_assign;

Re: How to assign value to macro variable from another variable?

Kurt_Bremser — Tue, 14 Sep 2021 10:52:52 GMT

Your code has a wrong %DO statement (no %TO) and misses a %END to close the %DO.

Re: How to assign value to macro variable from another variable?

PaigeMiller — Tue, 14 Sep 2021 10:55:08 GMT

Earlier, I asked for a concrete example showing how values are assigned to the different macro variables. I specifically said I do not want to see code. I don't know what %get_value does, so this isn't helping.

What I can see is this:

&i=1

then &var is assigned the value va.

What happens next (without writing code, what is the next thing that happens)? Then keep going through the entire example.

Re: How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 11:00:29 GMT

Yeah, When &i = 1, var = va, I get t = 'Hi, 1' in the %get_value function.

Then I do this in do macro %batch_assign;

%let &var = &t;

I want globally va = 'Hi, 1'.

My SAS is on the company cloud environment, can't just copy code from there. I'm pretty sorry to make it looks complex here. Thanks, Sir.

Re: How to assign value to macro variable from another variable?

PaigeMiller — Tue, 14 Sep 2021 11:18:28 GMT

First, you almost never want macro variable values to be enclosed in quotes. That's just not necessary.

Next, you say "I get t = 'Hi, 1' in the %get_value function." Does this mean that macro variable &t is assigned the value of 'Hi, 1'? Because the way you wrote it when you referred to t, it seems like it is not a macro variable.

Since I still don't know what %get_value does, perhaps adding in

%global t;

right at the top of the code will allow &t to pass its value into your command

%let &var=&t;

Re: How to assign value to macro variable from another variable?

Kurt_Bremser — Tue, 14 Sep 2021 11:16:50 GMT

Is this what you want?

%let vars = va|vb|vc;

%macro assign;
%do i = 1 %to %sysfunc(countw(&vars.,|));
  %global %scan(&vars,&i,|);
  %let %scan(&vars,&i,|) = Hi, &i.;
%end;
%mend;
%assign

%put &=va &=vb &=vc;

Re: How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 11:21:16 GMT

Thanks,Sir. Guess I know what's going on here.

Since I %let &var = &t; in the Macro %batch_assign, I was thinking SAS won't allow %let resolve a variable, All I need is just state &var global before I pass in values(coz generally if you use %let globally, it's OK not to make a statement, it doesn't hit me until you say so)...

It's solved now, Thank you very much!

Re: How to assign value to macro variable from another variable?

kimmygzc — Tue, 14 Sep 2021 11:26:28 GMT

Oh, yes! This avoid a transit assignment, Thank you, Sir!

Re: How to assign value to macro variable from another variable?

Kurt_Bremser — Tue, 14 Sep 2021 11:35:11 GMT

Alternatively, you can do it in a DATA step:

data _null_;
vars = "&vars";
do i = 1 to countw(vars,"|");
  call symputx(scan(vars,i,"|"),catx(" ","Hi,",i),"g");
end;
run;