Executes an R script that has the ability to access feature data from a temporary R data frame.

How does it work?

Input data is set up in the form of tables that will become R data frames. R data frames are tables similar to those of a relational database that support columns of varying types. More information on R data frames can be found at:


This transformer requires that the system has R and the sqldf package installed in order to run. See Installing R in the Usage Notes section.

Any number of input data frames can be created, and each will be assigned an input port. Any features can be routed to that input port as long as they supply values for each column defined for the table. The R Script can involve any and all data frames and columns defined in the input. Output is taken from the fmeOutput data frame that the user can populate with the results of statistical analysis on any of the input tables.

Any number of input ports can be created either by connecting to the Connect Input port or by editing the transformer properties and manually adding new inputs or by importing port definitions from existing feature types. Once imported the table definitions will not automatically change as their source changes, in the event an attribute name is changed upstream the name of the corresponding table column will need to be manually adjusted in the table parameters. Users will need to manually expose the output attributes which will be imported from the column names of the fmeOutput data frame at runtime.

The success of the translation relies on the user supplying a valid R Script that adheres to proper R syntax. A guide on the R Language is listed below:


To learn more about how to use R and to get ideas for different types of statistical analysis that may be possible, the following links are recommended:




Usage Notes

Installing R

To use this transformer, you must install both R and the sqldf package. Using raster objects additionally requires the raster package.

Troubleshooting Tips

Specifying the R Interpreter

FME will try its best to find R as installed on your system; however, if R is installed in a non-default location, or you have multiple R interpreters installed, it may be necessary to specify the R Interpreter Path under Tools > FME Options > Translation > R Interpreter



Editing Transformer Parameters

Using a set of menu options, transformer parameters can be assigned by referencing other elements in the workspace. More advanced functions, such as an advanced editor and an arithmetic editor, are also available in some transformers. To access a menu of these options, click beside the applicable parameter. For more information, see Transformer Parameter Menu Options.

Defining Values

There are several ways to define a value for use in a Transformer. The simplest is to simply type in a value or string, which can include functions of various types such as attribute references, math and string functions, and workspace parameters. There are a number of tools and shortcuts that can assist in constructing values, generally available from the drop-down context menu adjacent to the value field.

Dialog Options - Tables

Transformers with table-style parameters have additional tools for populating and manipulating values.

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