R: A cluster future is a future whose value will be resolved...

ClusterFuture-class {future} | R Documentation

## A cluster future is a future whose value will be resolved asynchronously in a parallel process

### Description

A cluster future is a future whose value will be resolved asynchronously in a parallel process

### Usage

    ClusterFuture(expr = NULL, envir = parent.frame(), substitute = FALSE,
      globals = TRUE, packages = NULL, local = !persistent, gc = FALSE,
      persistent = FALSE, workers = NULL, user = NULL, master = NULL,
      revtunnel = TRUE, homogeneous = TRUE, ...)

    MultisessionFuture(expr = NULL, envir = parent.frame(),
      substitute = FALSE, globals = TRUE, persistent = FALSE,
      local = !persistent, workers = NULL, ...)

### Arguments

`expr` | An R expression.
`envir` | The environment from where global objects should be identified.
`substitute` | If TRUE, argument `expr` is `substitute()`:ed, otherwise not.
`globals` | (optional) a logical, a character vector, or a named list to control how globals are handled. For details, see section 'Globals used by future expressions' in the help for `future()`.
`packages` | (optional) a character vector specifying packages to be attached in the R environment evaluating the future.
`local` | If TRUE, the expression is evaluated such that all assignments are done to local temporary environment, otherwise the assignments are done to the global environment of the R process evaluating the future.
`gc` | If TRUE, the garbage collector run (in the process that evaluated the future) after the value of the future is collected. Some types of futures ignore this argument.
`persistent` | If FALSE, the evaluation environment is cleared from objects prior to the evaluation of the future.
`workers` | A `cluster` object, a character vector of host names, a positive numeric scalar, or a function. If a character vector or a numeric scalar, a `cluster` object is created using `makeClusterPSOCK(workers)`. If a function, it is called without arguments when the future is created and its value is used to configure the workers. The function should return any of the above types.
`user` | (optional) The user name to be used when communicating with another host.
`master` | (optional) The hostname or IP address of the master machine running this node.
`revtunnel` | If TRUE, reverse SSH tunneling is used for the PSOCK cluster nodes to connect back to the master R process. This avoids the hassle of firewalls, port forwarding and having to know the internal / public IP address of the master R session.
`homogeneous` | If TRUE, all cluster nodes is assumed to use the same path to ‘Rscript’ as the main R session. If FALSE, the it is assumed to be on the PATH for each node.
`...` | Additional named elements passed to `Future()`.

### Value

`ClusterFuture()` returns an object of class `ClusterFuture`.

`MultisessionFuture()` returns an object of class `MultisessionFuture`, which inherits from `ClusterFuture`.

### See Also

To evaluate an expression using "cluster future", see function `cluster()`.

[Package future version 1.9.0 Index]