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Y may be any array.  X must be a simple scalar or vector of non-negative integers.  R is an array of shape X whose elements are taken from Y in row-major sequence and repeated cyclically if required.  If Y is empty, R is composed of fill elements of Y (⊂∊⊃Y with ⎕ml←0).  If X contains at least one zero, then R is empty.  If X is an empty vector, then R is scalar.

Examples

      2 3⍴⍳8
1 2 3
4 5 6
 
      2 3⍴⍳4
1 2 3
4 1 2
 
      2 3⍴⍳0
0 0 0
0 0 0