Ab Initio : IN and NOT IN

You can create a vector with the possible values and then use operator
"member" to get that the same functionality in Abinitio. For example, lets
say u have 5 values to compare with, output field name is check_value then
in reformat, u can try as
let decimal("|")[5] temp_vec = [vector 10, 12, 13, 23, 33];
out.check_value :: if(in.field_name member temp_vec) "Yes" else "No".
OR if there are 30 or 40 values ..i mean more data to compare, create a
lookup file and perform the operation.
Ref : http://datawarehouse.ittoolbox.com/groups/technical-functional/abinitio-l/in-and-not-in-2890661