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# orch.export

Makes R objects from a user's local R session available in the Hadoop execution environment, so that they can be referenced in MapReduce jobs.

Usage

    orch.export(...)

Arguments

. . .

  One or more variables, data frames, or other in-memory objects, by name or as an explicit definition, in a comma-separated list.

Usage Notes

You can use this function to prepare local variables for use in `hadoop.exec` and `hadoop.run` functions. The `mapper`, `reducer`, `combiner`, `init`, and `final` arguments can reference the exported variables.

Return Value

A list object

See Also

`hadoop.exec`, `hadoop.run`

Example

This code fragment shows `orch.export` used in the `export` argument of the `hadoop.run` function:

    hadoop.run(x,
        export = orch.export(a=1, b=2),
        mapper = function(k,v) {
            x <- a + b
            orch.keyval(key=NULL, val=x)
        }
    )

The following is a similar code fragment, except that the variables are defined outside the `hadoop.run` function:

    a=1
    b=2
    hadoop.run(x,
        export = orch.export(a, b),
        .
        .
        .
    )