SAS and BI: getting the variable rules by obs

[LineMoon]

I have a sas data toto.

==> It contains the variables: V1, V2, ....Vn, W

==> I want to get the rule of W,  I know that W can be

From obs = 1 to  u

w= Vi+Vj*Vm+Vg+.....

From obs=u+1 to n

w=e*Vp*Vy+Vh

.................

.................

I am looking for an automatic solution to identify the rules of the variable W for every observation.

Thank you

[Quentin]

It's not clear to me what you want. I suggest you add a sample dataset (maybe with just V1 V2 V3 W, and about 10 observations), and the solution you would want from that dataset.

[LineMoon]

I want to extract the rules of W by observations

[Quentin]

Sorry, still not clear to me what you mean by that. Again, I think showing some example data and desired result might help.