topic Re: Output array variable name(s) into one column in SAS Programming

Output array variable name(s) into one column

Altal — Wed, 30 Oct 2013 21:18:59 GMT

I have multiple date variables (date1, date2, ..., date8) that I am taking the earliest of them (min (of date1 - date8)) and using for censoring in a time-to-event analysis.

Some dates could be the same; others may be missing.

I'd like to output which date(s) were the minimum, thus used for censoring and output VNAME. Is there a way, by arrays maybe to output a one column that tells which of these dates equaled the minimum?

for example:

date1 date2 date3 date4 date5 ... minDate

1/1/12 . 5/7/13 . . date1

. 6/5/12 . 6/5/12 . date2/date4

and so on ...

Thanks

Re: Output array variable name(s) into one column

Peter_C — Wed, 30 Oct 2013 22:04:23 GMT

have a look at the WHICHN() function

Re: Output array variable name(s) into one column

FriedEgg — Wed, 30 Oct 2013 22:10:27 GMT

data foo;

format date1-date8 yymmdd10.;

array date[8];

do i = 1 to 1000;

call missing( of date

);

do j = 1 to 8;

if ranuni(4350982)<2/5 then date='01JAN2013'd + floor( (1+today()-'01JAN2013'd)*ranuni(567890) );

end;

output;

end;

drop i j;

run;

data bar;

array date[8];

length minDate $ 200;

format min yymmdd10.;

set foo;

min=min(of date

);

if min > 0 then do;

_n_ = whichn( min , of date

) ;

do while( _n_ > 0 );

minDate=catx( '/' , minDate , vname( date[_n_] ) );

call missing( date[_n_] );

_n_ = whichn( min , of date

) ;

end;

run;

Re: Output array variable name(s) into one column

snoopy369 — Wed, 30 Oct 2013 22:35:20 GMT

Here are two ways to do it. The first only picks one minimum; the second is a bit more work but will pick multiple.

WHICHN() function tells you which argument after the first has the value of the first argument (only tells you the first one, though). For both solutions, VNAME() tells you the variable name of the variable in the array.

data have;

input

date1 date2 date3 date4 date5;

informat date1-date5 MMDDYY8.;

format date1-date5 DATE9.;

datalines;

1/1/12 . 5/7/13 . .

. 6/5/12 . 6/5/12 .

;;;;

run;

data want;

set have;

array dates date1-date5;

format minDateVal $200.;

minDate = whichn(min(of dates

),of dates

);

if (1 le minDate lt dim(dates)) then

minDateVal = vname(dates[mindate]);

end;

put minDateVal=;

run;

data want;

set have;

array dates date1-date5;

format minDateVal $200.;

do _t = 1 to dim(dates);

if dates[_t] = min(of dates

) then

minDateVal = catx(',',minDateVal,vname(dates[_t]));

end;

run;

Re: Output array variable name(s) into one column

Altal — Wed, 30 Oct 2013 22:42:49 GMT

Thanks guys; the below has worked fine for me...

data have;

set have;

array _dates date1..... date8;

array _dateName $ datename1... datename8;

do over _dates;

if _dates= MinDate then _dateName=VNAME(_dates);

end;

minimumDateNames=catx('/', of datename1-datename8 );

run;

Re: Output array variable name(s) into one column

art297 — Wed, 30 Oct 2013 23:27:03 GMT

My pet peeve of the day: a couple of your colleagues gave you good solutions, but you opted to post your own variant and declare it the correct answer. Okay, a poster CAN come up with the best answer to their own question, but your "correct" answer doesn't even do what you asked for

Re: Output array variable name(s) into one column

Altal — Thu, 31 Oct 2013 02:13:07 GMT

Hey Arther; sorry for your disappointment! snoopy's second part does what I wanted too, in addition to mine . To cheer up a bit, I changed the "correct" answer.

Re: Output array variable name(s) into one column

Tom — Thu, 31 Oct 2013 02:18:57 GMT

I think that looping over the array of dates is probably clearer when you want to find ALL of the examples that match the minimum. The extra array of variable names is not needed since you can accumulate the names right into the target variable as you detect them.

data have;

informat date1-date8 date9.;

format date1-date8 date9.;

input date1-date8;

cards;

01jan2013 02jan2013 01jan2013 . . . . .

run;

data want;

set have;

array _dates date1 - date8;

length mindate 8 minimumDateNames $200 ;

mindate = min(of _dates(*));

format mindate date9.;

do over _dates;

if _dates= MinDate then

minimumDateNames=catx('/',minimumDateNames,VNAME(_dates))

;

end;

put (_all_) (=/);

run;

date1=01JAN2013

date2=02JAN2013

date3=01JAN2013

date4=.

date5=.

date6=.

date7=.

date8=.

mindate=01JAN2013

minimumDateNames=date1/date3

Re: Output array variable name(s) into one column

Altal — Thu, 31 Oct 2013 02:31:50 GMT

Makes perfect sense. Thanks for clarification Tom!