From jaroslav.kuchar at fit.cvut.cz  Sun Dec  6 18:36:16 2015
From: jaroslav.kuchar at fit.cvut.cz (=?UTF-8?Q?Ing=2E_Jaroslav_Kucha=C5=99?=)
Date: Sun, 06 Dec 2015 18:36:16 +0100
Subject: [Rd] How to efficiently share data (a dataframe) between R and Java
Message-ID: <466cd25ef41dbefc2ee18c725a581e78@imap.fit.cvut.cz>

Dear all,

in our ongoing project we use Java implementations of several
algorithms. We also provide a ?wrapper? implemented as an R package
using rJava (https://github.com/jaroslav-kuchar/rCBA). Based on our
recent experiments, the significant portion of time is spent on copying
a dataframe from R to Java. The Java implementation needs access to the
source dataframe. 

I have tested several approaches: calling Java method row-by-row;
serialize the whole data-frame to a temp file and parsing in Java; or
row binding to a single vector and calling a single Java method. Each
approach has its limitations e.g. time-consuming row-by-row copying,
serialization and parsing performance or memory limitations of a single
vector. 

Is there an efficient approach how to copy a dataframe from R to Java
and another one from Java to R?

Thanks for any help you can provide...

Regards,
Jaroslav



[Rd] How to efficiently share data (a dataframe) between R and Java
=?UTF-8?Q?Ing=2E_Jaroslav_Kucha=C5=99?=