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Effect and Restrictions

Effect:
The description of the exit value of destination is identical to the description after execution of a Shift schedule (see section A.4), except that the constant shift is replaced by


  shift [
$ x_0, \ldots , x_{\mbox{\tt dim-1}}, x_{\mbox{\tt dim+1}}, \ldots , x_{R - 1}$]
Value restrictions:
The value of dimension must be in the range 0, ...,$ R$-1 where $ R$ is the rank of the source array.
Type restrictions:
The elements of the source and destination arrays must have the same type if primitive. If the element types are Object, subtypes of all objects referenced by elements of the source array must be assignable to elements of the destination array.
Shape restrictions:
The source and destination array must have the same shape. The shape of the shift array must be obtained from the shape of the source array by deleting dimension dimension.
Alignment restrictions:
The source array must be aligned with the destination array. The shift-amount array should be aligned with the destination array, with replicated alignment over dimension dimension.
Containment restrictions:
The source array, the shift-amount array, and the destination array must be fully contained in the active progess group.
Overlap restrictions:
In-place updates are not allowed.
Replicated data:
If the arrays have replicated mapping, values for individual copies of the destination are generally taken from the nearest copy of the corresponding source array element. The definition of ``nearest'' is implementation dependent. This schedule does not implement a broadcast--consistent replication of copies in the destination array relies on consistency of copies of the source array.

next up previous contents
Next: WriteHalo Up: Skew Previous: Skew   Contents
Bryan Carpenter 2004-06-09