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