R - STATISTICAL COMPUTING¶
R is a language and environment for statistical computing and graphics. It is a GNU project which is similar to the S language and environment which was developed at Bell Laboratories (formerly AT&T, now Lucent Technologies) by John Chambers and colleagues. R can be considered as a different implementation of S. There are some important differences, but much code written for S runs unaltered under R. R provides a wide variety of statistical (linear and nonlinear modelling, classical statistical tests, time-series analysis, classification, clustering, ...) and graphical techniques, and is highly extensible. The S language is often the vehicle of choice for research in statistical methodology, and R provides an Open Source route to participation in that activity. One of R’s strengths is the ease with which well-designed publication-quality plots can be produced, including mathematical symbols and formulae where needed. Great care has been taken over the defaults for the minor design choices in graphics, but the user retains full control. R is available as Free Software under the terms of the Free Software Foundation’s GNU General Public License in source code form. It compiles and runs on a wide variety of UNIX platforms and similar systems (including FreeBSD and Linux), Windows and MacOS.
Following instructions are meant for science gateway maintainers while generic users can skip this section. To install the portlet it is enough to install the war file into the application server and then configure the infrastructure settings into the portlet preferences pane.
Preferences are splitted in three separate parts: Generic, Infrastructures and the application execution setting. The generic part contains the Log level which contains one of following values, sorted by decreasing level: info, debug, warning and error. The Application Identifier refers to theId field value of the GridEngine ‘UsersTracking’database table: GridInteractions. The infrastructure part consists of different settings related to the destination of users job execution. The fields belonging to this category are:
Enable infrastructure: A true/false flag which enables or disable the current infrastructure;
Infrastructure Name: The infrastructure name for these settings;
Infrastructure Acronym: A short name representing the infrastructure;
BDII host: The Infrastructure information system endpoint (URL). Infrastructure preferences have been thought initially for the elite Grid based infrastructures;
WMS host: It is possible to specify which is the brokering service endpoint (URL);
Robot Proxy values: This is a collection of several values which configures the robot proxy settings (Host, Port, proxyID, VO, Role, proxy renewal);
Job requirements: This field contains the necessary statements to specify a job execution requirement, such as a particular software, a particular number of CPUs/RAM, etc.
Actually, depending on the infrastructure, some of the fields above have an overloaded meaning. Please contact the support for further information or watch existing production portlet settings.
The usage of the portlet is simple; the user can select to upload a local R macro file selecting the Browse button in the Application input file section, or insert inside the text field the R macro text by pasting a text or editing directly on the larger text box below. The job identifier text is a human readable values that users will use to keep track of any job execution. Following buttons: Demo, Submit, Reset values and About are respectively:
Demo - Fills the Macro Text box with an R-Macro example
Submit - Executes the given macro on the distributed infrastructure
Reset - Resets the input form
About - Gives an overview of the portlet