Global addition
S = gplus(X)
S = gplus(X,targetlab)
S = gplus(X) returns the addition of the variant array
X from each worker. The result S is
replicated on all workers.
S = gplus(X,targetlab) performs the addition, and places the
result into S only on the worker indicated by
targetlab. S is set to
[] on all other workers.
With four workers,
S = gplus(labindex)
calculates S = 1 + 2 + 3 + 4, and returns 10
on all four workers.