Documentation

codistributed

Create codistributed array from replicated local data

Syntax

C = codistributed(X)
C = codistributed(X,codist)
C = codistributed(X,lab,codist)
C = codistributed(C1,codist)

Description

C = codistributed(X) distributes a replicated array X using the default codistributor, creating a codistributed array C as a result. X must be a replicated array, that is, it must have the same value on all workers. size(C) is the same as size(X).

C = codistributed(X,codist) distributes a replicated array X using the distribution scheme defined by codistributor codist. X must be a replicated array, namely it must have the same value on all workers. size(C) is the same as size(X). For information on constructing codistributor objects, see the reference pages for codistributor1d and codistributor2dbc.

C = codistributed(X,lab,codist) distributes a local array X that resides on the worker identified by lab, using the codistributor codist. Local array X must be defined on all workers, but only the value from lab is used to construct C. size(C) is the same as size(X).

C = codistributed(C1,codist) accepts an array C1 that is already codistributed, and redistributes it into C according to the distribution scheme defined by the codistributor codist. This is the same as calling C = redistribute(C1,codist). If the existing distribution scheme for C1 is the same as that specified in codist, then the result C is the same as the input C1.

Tips

gather essentially performs the inverse of codistributed.

Examples

Create a 1000-by-1000 codistributed array C1 using the default distribution scheme.

spmd
    N = 1000;
    X = magic(N);          % Replicated on every worker
    C1 = codistributed(X); % Partitioned among the workers
end

Create a 1000-by-1000 codistributed array C2, distributed by rows (over its first dimension).

spmd
    N = 1000;
    X = magic(N);
    C2 = codistributed(X,codistributor1d(1));
end
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