pvm_reduce — Performs a reduce operation over members of the specified group
[buff, info] = pvm_reduce(func, buff, msgtag, group, rootginst)
data. Should be : Max, Min, Sum or Pro.
the root will be overwritten with the result of the reduce operation over the group.
should be >= 0. It allows the user's program to distinguish between different kinds of messages.
string, group name of an existing group.
result.
less than zero indicate an error.
pvm_reduce performs global operations such as max, min,
sum or product over all the tasks in a group. All group members
call pvm_reduce with their local data, and the result of
the reduction operation appears on the user specified root
task root. The root task is identified by its instance
number in the group.
Max and Min are implemented for scalar datatypes (double, complex). For complex values the minimum [maximum] is that complex pair with the minimum [maximum] modulus. Sum and Product are implemented for scalar datatypes.
Note: pvm_reduce does not block. If a task calls pvm_reduce and then leaves the group before the root has called pvm_reduce an error may occur.