While installing "car" package in Rstudio in Ubuntu, I faced an error saying that dependencies "nloptr","lme4" and one more, are not installed. So I started installing "nloptr" but I faced this error-
configure: Need to download and build NLopt
trying URL 'http://ab-initio.mit.edu/nlopt/nlopt-2.4.2.tar.gz'
Error in download.file(url = "http://ab-initio.mit.edu/nlopt/nlopt-
2.4.2.tar.gz", :
cannot open URL ' '
Execution halted
/bin/tar: This does not look like a tar archive
gzip: stdin: unexpected end of file
/bin/tar: Child returned status 1
/bin/tar: Error is not recoverable: exiting now
Warning message:
In untar(tarfile = "nlopt-2.4.2.tar.gz") :
'/bin/tar -xf 'nlopt-2.4.2.tar.gz'' returned error code 2
configure: Starting to install library to
/tmp/RtmpSeLv7g/R.INSTALL18a67910d582/nloptr/nlopt-2.4.2
./configure: line 3325: cd: nlopt-2.4.2: No such file or directory
System hangs after last line and when I restart after some time, "nloptr" is not installed and hence I am unable to install "car" package. I have updated R version and URL in error is working in browser. Please help me. Thanks in advance.