我是R和cassandra的新手，我正在尝试安装rcassandra软件包。在rforge.net网站上，它说：
> install.packages('RCassandra',,'http://www.rforge.net/')
Warning: unable to access index for repository http://www.rforge.net/src/contrib
Warning message:
package ‘RCassandra’ is not available (for R version 3.1.0)
尝试使用其他存储库
> install.packages('RCassandra',repo='http://cran.cnr.Berkeley.edu/')
Installing package into ‘/home/as/R/x86_64-redhat-linux-gnu-library/3.1’
(as ‘lib’ is unspecified)
Warning: unable to access index for repository http://cran.cnr.Berkeley.edu/src/contrib/
Warning message:
package ‘RCassandra’ is not available (for R version 3.1.0)
我尝试从命令行安装，但这确实似乎有效：
> sudo R CMD INSTALL RCassandra_0.1\-3.tar.gz * installing to library ‘/home/as/R/x86_64-redhat-linux-gnu-library/3.1’ * installing *source* package ‘RCassandra’ ... ** package ‘RCassandra’ successfully unpacked and MD5 sums checked ** libs gcc -m64 -std=gnu99 -I/usr/include/R -DNDEBUG -I/usr/local/include -fpic -O2 -g -pipe -Wall -Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector --param=ssp-buffer-size=4 -m64 -mtune=generic -c cass.c -o cass.o cass.c:1: sorry, unimplemented: 64-bit mode not compiled in make: *** [cass.o] Error 1 ERROR: compilation failed for package ‘RCassandra’ * removing ‘/home/as/R/x86_64-redhat-linux-gnu-library/3.1/RCassandra
那我该如何安装包呢？我可以在网站上看到包裹