User`s guide

11 Functions — Alphabetical List

11-78

exist

Check whether Composite is defined on workers

Syntax

h = exist(C,labidx)

h = exist(C)

Description

h = exist(C,labidx) returns true if the entry in Composite C has a defined value on

the worker with labindex labidx, false otherwise. In the general case where labidx

is an array, the output h is an array of the same size as labidx, and h(i) indicates

whether the Composite entry labidx(i) has a defined value.

h = exist(C) is equivalent to h = exist(C, 1:length(C)).

If exist(C,labidx) returns true, C(labidx) does not throw an error, provided that

the values of C on those workers are serializable. The function throws an error if any

labidx is invalid.

Examples

Define a variable on a random number of workers. Check on which workers the

Composite entries are defined, and get all those values:

spmd

if rand() > 0.5

c = labindex;

end

ind = exist(c);

cvals = c(ind);