Gather

From Mesham
Revision as of 15:44, 15 April 2019 by Polas (talk | contribs) (4 revisions imported)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
Jump to navigationJump to search

Syntax

gather[elements,root]

Semantics

Gather a number of elements (equal to elements) from each process and send these to the root process.

Example

function void main() {
   var x:array[Int,12] :: allocated[single[on[2]]];
   var r:array[Int,3] :: allocated[multiple[]];
   var p;
   par p from 0 to 3 {
      (x::gather[3,2]):=r;
   };
};

In this example, the variable x is allocated on the root process (2) only. Whereas r is allocated on all processes. In the assignment all three elements of r are gathered from each process and sent to the root process (2) and then placed into variable x in the order defined by the source's PID.

Since: Version 0.41b