RETAIN question

[Cello23]

Hi,

i have this table:

KEY	CAU
2335083090018500	M88
33111356428352800	M88
33111275803210300	M88
33111381165566500	M88
33111708996242600	M88
33111708996242600	M90
2214196DL51H86501	M88
2214196DL51H86501	M90
33111230975677500	M88
33111230975677500	M90
3311359190969000	M88
3311359190969000	M90
33111380983028300	M88
33111380983028300	M90
503440K7QD3L18858	M88
22158083090018500	M88
503440K7QD3L18858	M90
2215083090018500	M90
33111208999140500	M88

I want create a new column (RESULT) with value "YES" when the value of column key is equal to previous value and the value  of column CAU is equal at 'M90' and  previous value is  equal to 'M88', this is example:

KEY	CAU	RESULT
2335083090018500	M88
33111356428352800	M88
33111275803210300	M88
33111381165566500	M88
33111708996242600	M88
33111708996242600	M90	YES
2214196DL51H86501	M88
2214196DL51H86501	M90	YES
33111230975677500	M88
33111230975677500	M90	YES
3311359190969000	M88
3311359190969000	M90	YES
33111380983028300	M88
33111380983028300	M90	YES
503440K7QD3L18858	M88
22158083090018500	M88
503440K7QD3L18858	M90
2215083090018500	M90
33111208999140500	M88

Can someone give me a help to create a data step with retain function?

Thanks!!!!

[LinusH]

Use retain to create two new variables, like key_ret and cau_ret.

Assign them the current observation values last in the data step, after any conditional assignments.

[ballardw · Accepted solution]

You could use RETAIN but this is what the LAG function which looks at previous values.

data want;

   set have;

   Lkey = lag(key);

   LCAU = lag(CAU);

   if Lkey=key and CAU='M90' and LCau='M88' then Result='YES';

   drop Lkey Lcau;

run; 

[Cello23]

Perfect!!!! thanks!!!

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