Variable is uninitialized after using PROC EXPAND

[Phil_NZ]

Hi all,

Today, after using proc expand to generate a variable, afterwards, I receive the note that the created variable is uninitialized.

The code is

proc expand data=agg_amihud_ew method=none;
	convert _FREQ_=lag_freq / transformout= (lag 1);
run;

data agg_amihud_ew_f;
set agg_amihud_ew;
 agg_amh_ew_final=agg_amh_ew_country*_FREQ_/lag_freq;
run;

The note is

28         proc expand data=agg_amihud_ew method=none;
29         	convert _FREQ_=lag_freq / transformout= (lag 1);
30         run;

NOTE: The data set WORK.DATA18 has 127 observations and 7 variables.
NOTE: PROCEDURE EXPAND used (Total process time):
      real time           0.02 seconds
      cpu time            0.01 seconds
      

31         
32         data agg_amihud_ew_f;
33         set agg_amihud_ew;
34          agg_amh_ew_final=agg_amh_ew_country*_FREQ_/lag_freq;
35         run;

NOTE: Variable lag_freq is uninitialized.
NOTE: Missing values were generated as a result of performing an operation on missing values.
      Each place is given by: (Number of times) at (Line):(Column).
      7 at 34:37     120 at 34:44   

When I read the log, I see it is because the proc expand creates a new dataset (DATA18) having different name with the original one(agg_amihud_ew), Could you please help me to sort it out (force PROC EXPAND create the new dataset replace the original one with the same name)?

Warm regards.

[Kurt_Bremser · Accepted solution]

As always, read the documentation 

You need to use the OUT= option to set the name of the output dataset.