collect {RGMQL} | R Documentation

## Method collect

### Description

Wrapper to GMQL MATERIALIZE operator

It saves the content of a dataset that contains samples metadata and regions. It is normally used to persist the content of any dataset generated during a GMQL query. Any dataset can be materialized, but the operation can be time-consuming. For best performance, materialize the relevant data only.

### Usage

    ## S4 method for signature 'GMQLDataset'
    collect(x, dir_out = getwd(), name = "ds1")

### Arguments

`x` | GMQLDataset class object
`dir_out` | destination folder path. By default it is the current working directory of the R process
`name` | name of the result dataset. By default it is the string "ds1"

### Details

An error occures if the directory already exist at the destination folder path

### Value

None

### Examples

    ## This statement initializes and runs the GMQL server for local execution
    ## and creation of results on disk. Then, with system.file() it defines
    ## the path to the folder "DATASET" in the subdirectory "example"
    ## of the package "RGMQL" and opens such file as a GMQL dataset named
    ## "data" using CustomParser

    init_gmql()
    test_path <- system.file("example", "DATASET", package = "RGMQL")
    data = read_gmql(test_path)

    ## The following statement materializes the dataset 'data', previoulsy read,
    ## at the specific destination test_path into local folder "ds1" opportunely
    ## created

    collect(data, dir_out = test_path)

[Package RGMQL version 1.2.0 Index]