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@parallel

A parallel for loop of the form :

@parallel [reducer] for var = range
    body
end

The specified range is partitioned and locally executed across all workers. In case an optional reducer function is specified, @parallel performs local reductions on each worker with a final reduction on the calling process.

Note that without a reducer function, @parallel executes asynchronously, i.e. it spawns independent tasks on all available workers and returns immediately without waiting for completion. To wait for completion, prefix the call with @sync, like :

@sync @parallel for var = range
    body
end

Examples

"""
    @parallel [reducer] for var = range

A parallel for loop of the form:

@parallel [reducer] for var = range
    body
end

The specified range is partitioned and locally executed across all workers. In case an optional reducer function is specified, @parallel performs local reductions on each worker with a final reduction on the calling process.

Note that without a reducer function, @parallel executes asynchronously, i.e. it spawns independent tasks on all available workers and returns immediately without waiting for completion. To wait for completion, prefix the call with @sync, like:

@sync @parallel for var = range
    body
end

Examples:

1. Parallel sum computation:

   julia> @parallel for i = 1:10
              @show i
              i
          end

   In this example, the loop executes in parallel across available workers, printing and returning the values of i. No reducer function is specified.

2. Parallel reduction using a custom reducer function:

   julia> reducer = (x, y) -> x + y  # Custom reducer function
   julia> @parallel reducer for i = 1:10
              @show i
              i
          end

   Here, the loop executes in parallel across workers, and each worker performs a local reduction using the custom reducer function. The final reduction is done on the calling process.

3. Waiting for completion using @sync:

   julia> @sync @parallel for i = 1:10
              @show i
              i
          end

   This example uses @sync to wait for the completion of all parallel tasks before proceeding.

Note: Ensure that the necessary worker processes are available before using @parallel.```

See Also

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