Crash when executing R script

Question

Hi *,

we set up a new function in the function catalogue which has two input datasets and one "text"-output. We put in the following example R-script:

a <- 42

Whenever we execute the script, Knowage crashes. The catalina-logfile can be found here: https://pastebin.com/LegXd5sm

Thanks

Sebastian

Answer 1

Hi,

    installation of the following components is required for using data mining engine within R language:
• R
• R Studio
• rJava
The first two components have to be installed via the rpm command and the third via the RStudio GUI.

Let's suppose that Knowage has been installed by Linux user tomcat.

Once retrieved the RPM files and rJava archive, open the folder and launch the commands:

rpm -Uvh ./R-3.2.2-1.el6.x86_64.rpm
yum install --nogpgcheck rstudio-server-rhel-0.99.486-x86_64.rpm
cp ./RStudio/rJava_0.9-8.tar.gz $TOMCAT_HOME
chown tomcat $TOMCAT_HOME/rJava_0.98.tar.gz
chown -R tomcat.root /usr/lib64/R/library && chmod -R 775 /usr/lib64/R/library
chown -R tomcat.root /usr/share/doc/R-3.2.2 && chmod -R 775 /usr/share/doc/R-3.2.2

Type http://<server_ip_or_machine_name>:8787/ in the browser, you get the login page of R Studio.
Then log in with the user credentials used for the Tomcat 7 installation: tomcat / <tomcat_user_password>.
Install rJava package via R Studio GUI, remembering to answer NO when asked to create a personal library in the user home (that can be found under $HOME/RStudio/log). This way, rJava will be installed in the directory /usr/lib64/R/library/rJava.

Finally, edit the TOMCAT_HOME/bin/setenv.sh adding:

export R_HOME=/usr/lib64/R
export LD_LIBRARY_PATH=/usr/lib64/R/library/rJava/jri

Best regards,

Francesco

Comments

Thanks, I thought we already installed R, but seems like that is not the case. We'll test this and will report back. (Still, Knowage should maybe not crash just because a "plugin" is missing ...? :-) )

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You are right. We are studying why that happens and make that part more robust. Thanks to let us know!

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Hello, I just wanted to know that you may want to update also the installation instructions to mention RStudio and rJava as they are at the moment a bit short on that point.

http://download.forge.ow2.org/knowage/Knowage-CE-Installer-GettingStarted.pdf

https://github.com/KnowageLabs/Knowage-Server/tree/master/doc/admin

Or maybe I'm looking at the wrong documents?

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Yes, you are right. I will open an issue about this. Thanks!