Index with Axes R←{X}⌷[K]Y

X must be a scalar or vector of depth ≤2, of integers each ≥⎕IO. Y may be any array. K is a simple scalar or vector specifying axes of Y. The length of K must be the same as the length of X:

      (⍴,X) ≡ ⍴,K

In general, the result R is similar to that obtained by square-bracket indexing with elided subscripts. Items of K distribute items of X along the axes of Y. For example:

      I J ⌷[1 3] Y  ←→  Y[I;;J] 

Note that index with axis may be used with selective specification. ⎕IO is an implicit argument of index with axis.

Examples

     ⎕IO←1

     ⎕←CUBE←10⊥¨⍳2 3 4
111 112 113 114
121 122 123 124
131 132 133 134

211 212 213 214
221 222 223 224
231 232 233 234

      2⌷[1]CUBE
211 212 213 214
221 222 223 224
231 232 233 234

      2⌷[3]CUBE
112 122 132
212 222 232

      CUBE[;;2] ≡ 2⌷[3]CUBE
1
      (1 3)4⌷[2 3]CUBE
114 134
214 234

      CUBE[;1 3;4] ≡ (1 3)4⌷[2 3]CUBE
1

      (2(1 3)⌷[1 3]CUBE)←0 ⋄ CUBE ⍝ Selective assignment.
111 112 113 114
121 122 123 124
131 132 133 134

  0 212   0 214
  0 222   0 224
  0 232   0 234