Generating lags of multiple variables at once

[TalonHill]

Hello!  I have a question which I'm sure is very easy, but I'm stumped.

How do I generate lags of multiple variables at once?  I have 105 variables -- each variable I need to lag once and twice.

I've created an array, and tried a number of DO statements, but nothing seems to work.  Anyone have any ideas?

Thanks!

[AncaTilea]

Something like this could work. But you have to be careful with you first.keyword to reset all the lag values to . so it doesn't carry over the value from prior record...

but this piece of code should get you started:

proc sql;

    select cat("prev_",name,"= lag(",name,");") into: my_list separated by " "

    from dictionary.columns

    where libname = "SASHELP" & memname = "CLASS" ;

quit;

data temp;

    set sashelp.class;

    &my_list.;

run;

All you need to change is the name of your library (WORK?) and the name of the dataset. Make sure you use CAPS.

Good luck!

Anca

[ballardw]

array vars <your list of vars here>;

array L1vars <your list of vars prefixed with L1 here>;

array L2vars <your list of vars prefixed with L2 here>;

Do i = 1 to dim(vars);

     L1Vars = lag(vars);

     L2Vars = lag2(vars);

end;

drop i;

should work unless you make the do loop conditional.

The LAG2 variables will be blank for the first two records and the Lag variables blank on the first record.

[Ksharp]

Tow optional ways :

set x point=_n_-1

And

HashTable