# pure functions in nested select

I want to select certain rows from a list by using two nested Select commands

Select[List1, #[[2]] >=
Select[List2, #[[1]] == IntegerPart[2* PREVIOUS#[[1]] ]/2 &] &]


where by PREVIOUS#[[1]] I mean the first argument of the previous pure function (i.e. the argument of the list List1). I think this question may be duplicated, since I found that people solves this kind of problems using Function[], but I cannot figure out how (Sorry for my ignorance, I am new in Mathematica).

Cheers!

Using Function you can give the parameters a name:

Select[
List1,
Function[a, a[[2]] >= Select[
List2,
Function[b, b[[1]] == IntegerPart[2*a[[1]]]/2]
]]
]

• Thank you very much for that, I was not sure whether using "Function[]" and the "&" notation was exactly equivalent. And again, sorry for my stupid question! – Vazquez Jan 21 '15 at 14:54