topic Re: adding a separate condition to an array in SAS Programming

adding a separate condition to an array

jenim514 — Wed, 24 Feb 2016 22:12:37 GMT

I am looking to pull out observations with a specific ICD9 code "493" from either the variable PrincipleDiagnosis or any of the SecondaryDiagnosis2-SecondaryDiagnosis20. I have this array for the secondary diagnosis:

data want;

set have;

if principaldiagnosis=:493;

array secondarydiagnosis(*) secondarydiagnosis2-secondarydiagnosis20;

do i= 1 to dim(secondarydiagnosis);

if secondarydiagnosis(i)=: '493' then do;

output;

end;

run;

However, how can I also get this to check the variable PrincipalDiagnosis...

if principaldiagnosis=:'493'

in the same data step?

Thanks for your help!!

Re: adding a separate condition to an array

Reeza — Wed, 24 Feb 2016 22:24:21 GMT

Why separate it? Put the primary in your diagnosis list for secondary and include it in the loop.

You can also access it independently if needed by name.

Re: adding a separate condition to an array

jenim514 — Wed, 24 Feb 2016 22:42:02 GMT

I wish I understood arrays better...not sure how, where to include principaldiagnosis in the loop since it is a different variable.

data asthma_only;

set champs_j.table_C_MDR;

array primarydiagnosis secondarydiagnosis(*) secondarydiagnosis2-secondarydiagnosis20;

do i= 1 to dim(secondarydiagnosis);

if secondarydiagnosis(i)=: '493' then do;

if principaldiagnosis=:'493' then do;

output;

end;

run;

=== ERROR!!

Re: adding a separate condition to an array

jenim514 — Wed, 24 Feb 2016 22:49:58 GMT

or like this?

data want;

set have;

array diagnosis(*) primarydiagnosis secondarydiagnosis2-secondarydiagnosis20;

do i= 1 to dim(diagnosis);

if diagnosis(i)=: '493' then do;

output;

end;

run;

Re: adding a separate condition to an array

SAS_inquisitive — Wed, 24 Feb 2016 23:05:51 GMT

Array is nothing. It's just a of group of variables that you want perform similar operations on it.

Re: adding a separate condition to an array

Reeza — Wed, 24 Feb 2016 23:50:43 GMT

@jenim514 wrote:

or like this?

data want;

set have;

array diagnosis(*) primarydiagnosis secondarydiagnosis2-secondarydiagnosis20;

do i= 1 to dim(diagnosis);

if diagnosis(i)=: '493' then do;

output;

end;

end;

run;

Yes, you can just add the variable in to the list. Arrays are short cuts, nothing more, nothing less.

Re: adding a separate condition to an array

Astounding — Thu, 25 Feb 2016 00:03:12 GMT

Also consider this. If multiple diagnoses all begin with "493" you will output the same observation multiple times. To prevent that, you could add anothe statement immediately following the output:

output;

delete;

Re: adding a separate condition to an array

ChrisNZ — Thu, 25 Feb 2016 07:40:40 GMT

To avoid duplicates.

if diagnosis(i)=: '493' then do;
output;
leave;
end;

Re: adding a separate condition to an array

ChrisNZ — Thu, 25 Feb 2016 08:52:07 GMT

It is also possible to test the whole array in one go, for example like below.

The first data step runs twice as fast as the second one.

data HAVE;

retain PRIMARYDIAGNOSIS '495' SECONDARYDIAGNOSIS8 '493';

do I =1 to 1e7; output; end;

drop I;

run;

data WANT;

array DIAGNOSIS(*) $3 PRIMARYDIAGNOSIS SECONDARYDIAGNOSIS2-SECONDARYDIAGNOSIS20;

DSID=open('HAVE');

call set (DSID);

do until(RC);

RC=fetch(DSID);

if RC=0 and whichc('493', of DIAGNOSIS[*]) then output;

end;

RC=close(DSID);

run;

data WANT;

array DIAGNOSIS(*) $ PRIMARYDIAGNOSIS SECONDARYDIAGNOSIS2-SECONDARYDIAGNOSIS20;

set HAVE;

do I=1 to dim(DIAGNOSIS);

if DIAGNOSIS[I] =:'493' then do;

output;

leave;

end;

run;

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