# `↑` — First / Take

Function. Keys: `Alt-k`. Ranks: `∞` monadic, `1 ∞` dyadic

`↑Y` returns the first major item, like `0⊃Y`. On an enclosure it
returns the contained value. An empty leading axis gives a cell of fill.

``` bpl
↑[[1 2] [3 4 5]]  ⍝ 1 2
↑2 3⍴⍳6           ⍝ 0 1 2
↑⊂7               ⍝ 7
↑0 3⍴0            ⍝ 0 0 0
```

`N↑Y` takes leading items; negative `N` takes from the end. Overtake
inserts fill.

``` bpl
4↑1 2              ⍝ 1 2 0 0
¯4↑1 2             ⍝ 0 0 1 2
```

Vector counts apply to successive leading axes. `N↑⍠K Y` applies the
counts to axes `K`.

``` bpl
1 2↑2 3⍴⍳6         ⍝ 1 2⍴0 1
```

## Inverse

`↑⁻¹Y` encloses `Y`.

``` bpl
↑⁻¹5   ⍝ ⊂5
```