Why would "retain" in the data statement fail to reorder variables?

[iiibbb]

This does what I'd expect...

data sample;

input d c b a;

cards;

4 3 2 1

;

data retain_method;

retain a b c d;

set sample;

proc print;

run;

----------------------------

The following prints all variables, but fails to reorder them or drop the ones I don't want. 

Note:  Dataset work.a has a mixture of character, date, time, numerical values, and my retain statement is not calling them all because I want to drop them.

data b;

    set a;

    retain GPS_Date GPS_Time GPS_Second Name Speed Bearing Inclinatio East North Up Max_PDOP Max_HDOP  Northing Easting;

proc print data=b (obs=40);

run;

What am I doing wrong?

[art297 · Accepted solution]

In order for the retain statement to do what you want it must come BEFORE the set statement.  Similarly, if you want to drop some variables, you can do that in the set statement using the (drop=variablenamesseparatedbyspaces) option.