topic refer all elements in array in DROP statement in data step in SAS Programming

refer all elements in array in DROP statement in data step

Xin — Tue, 15 Sep 2015 20:33:07 GMT

Hello,

I was wondering if someone can help me with a question working with array in data step. I was trying to drop all elements in an array after the reshape. Here is what i've tried and it gave error message that i can't refer the array this way in DROP statement. Is there a way to do it? Thanks in advance. - Xin

data tmp;

set tmp2;

array wide{*} _numeric_;

drop wide{*};

run;

Re: refer all elements in array in DROP statement in data step

ballardw — Tue, 15 Sep 2015 21:18:14 GMT

If the purpose of this was to go from wide to narrow it likely is easier to KEEP the new variables. If there are lots of character variables to keep then use the _character_ variable list in the keep statement.

Re: refer all elements in array in DROP statement in data step

Haikuo — Tue, 15 Sep 2015 21:20:53 GMT

No, you can't do that as you have already figured out. The reason being non-executable statements such as 'Drop/Keep' works during the compiling stage, while Array statement works on execution stage. However, for the example you presented, you can do the following:

drop of _numeric_;

Re: refer all elements in array in DROP statement in data step

PGStats — Tue, 15 Sep 2015 21:32:41 GMT

drop _numeric_;
but that will also drop any new numeric variable created in the datastep.

Re: refer all elements in array in DROP statement in data step

data_null__ — Tue, 15 Sep 2015 21:34:33 GMT

You don't need OF unless it is a variable name. OF is the special function syntax.

Re: refer all elements in array in DROP statement in data step

Xin — Tue, 15 Sep 2015 21:34:40 GMT

Yes, as you've point out, KEEP statement can be troublesome when there are lot of char varibles to keep. KEEP _character_ works well. Thanks a lot.

Re: refer all elements in array in DROP statement in data step

Xin — Tue, 15 Sep 2015 21:36:20 GMT

The drop _numeric_ will drop the new variables i've created and won't work.

Re: refer all elements in array in DROP statement in data step

KachiM — Tue, 15 Sep 2015 22:31:35 GMT

Drop _numeric_ doesn't seem to be working. Here is a test:

data tmp; 
   set sashelp.class; 
   array wide[*] _numeric_; 
   do i = 1 to dim(wide);
      put wide[i] =;
   end;
   drop  _numeric_;
   put wide[*] =;
run;

Re: refer all elements in array in DROP statement in data step

Xin — Tue, 15 Sep 2015 22:49:14 GMT

It worked on my computer. The three numberical variables are dropped in tmp as indicated by DROP statement. The last PUT statement will generate the three variables in log.

Re: refer all elements in array in DROP statement in data step

KachiM — Tue, 15 Sep 2015 23:12:09 GMT

Yes TMP is OK.

Re: refer all elements in array in DROP statement in data step

Astounding — Thu, 17 Sep 2015 22:45:44 GMT

This statement works IF you place it properly:

drop _numeric_;

It should appear immediately after the ARRAY statement.

In a DATA step, _numeric_ changes meaning as the DATA step creates more numeric variables. So place the DROP statement after ARRAY, but before creating additional variables.

Re: refer all elements in array in DROP statement in data step

Xin — Mon, 21 Sep 2015 23:10:36 GMT

Thanks! This is the solution!