INTNX function-Why get null value in result??

[Ronein]

Hello

I am trying to use INTNX function to get one day after  date in start column.

Why am I getting null value ?(In following statement:

OneDay_after_start=INTNX ('day', start, 1);

Data tbl1;
informat start date9. end date9.;
format start date9. end date9.;
input mon start end;
cards;
1812 '21DEC2018'd '21Jan2019'd
1901 '22Jan2019'd '21Feb2019'd
1902 '22Feb2019'd '21Mar2019'd
;
run;


data tbl2;
set tbl1 end=eof;
if eof then output;
OneDay_after_start=INTNX ('day', start, 1);
call symput('xxx1',start);
call symput('xxx2',put(start,date9.));
call symput('xxx3',"'"||put(start,date9.)||"'d");

call symput('www1',OneDay_after_start);
call symput('www2',put(OneDay_after_start,date9.));
call symput('www3',"'"||put(OneDay_after_start,date9.)||"'d");
run;
%put &xxx1.;/*21602*/
%put &xxx2.;/*22FEB2019*/
%put &xxx3.;/*'22FEB2019'dt*/

%put &www1.;/*21603*/
%put &www2.;/*23FEB2019*/
%put &www3.;/*'23FEB2019'dt*/

[Shmuel]

To get the next day date you do

tomorrow = toady +1;

Sas date counts days from 01JAN1960 as zero. You don't need INTNX function.

[novinosrin]

Hi @Ronein 

To your why-

"Hello

I am trying to use INTNX function to get one day after  date in start column.

Why am I getting null value ?(In following statement:

OneDay_after_start=INTNX ('day', start, 1);"

Move your 

OneDay_after_start=INTNX ('day', start, 1);

Before 

if eof then output;

See the below

data tbl2;
set tbl1 end=eof;
OneDay_after_start=INTNX ('day', start, 1);
if eof then output;
/*OneDay_after_start=INTNX ('day', start, 1);*/
call symput('xxx1',start);
call symput('xxx2',put(start,date9.));
call symput('xxx3',"'"||put(start,date9.)||"'d");

call symput('www1',OneDay_after_start);
call symput('www2',put(OneDay_after_start,date9.));
call symput('www3',"'"||put(OneDay_after_start,date9.)||"'d");
run;

[Kurt_Bremser]

Your only output in this data step happens BEFORE any calculation takes place, therefore all new variables not contained in tbl1 will still be missing.

[ChrisNZ]

Also,

1. Use call symputx() for numeric variables to avoid messages in the log.

call symputx('xxx1',START); 

2. Your code is more efficient if you do nothing unless required to:

data TBL2;
  set TBL1 end=EOF;
  if EOF ;
  ONEDAY_AFTER_START=intnx('day', START, 1);
  call symputx()...
run;

3. For even more efficiency and if the table is large, fetch the number of observations and use option FIRSTOBS=

data _null_;
  call symputx('nobs',NOBS);
  stop;
  if 0 then set TBL1 nobs=NOBS;
run;

data TBL2;
  set TBL1 (firstobs=&nobs.);
  ONEDAY_AFTER_START=intnx('day', START, 1);
  call symputx()...
run;

[Tom]

If SAS knows the number of observations then you could use POINT=.  Just be careful not to put the data step into an infinite loop.

data x;
  if _n_>1 then stop;
  set sashelp.class point=nobs nobs=nobs;
run;