Useful Linux commands
Installing openmpi with pmix
Install zlib: sudo apt-get install zlib1g-dev
Download openmpi, ./configure --with-pmix, make, make install
Joining multiple files and compressing without losing quality
gs -sDEVICE=pdfwrite -dCompatibilityLevel=1.4 -dPDFSETTINGS=/ebook -dNOPAUSE -dQUIET -dBATCH -sOutputFile=output.pdf input1.pdf input2.pdf input3.pdf input4.pdf
Useful packages
Latex style file
sudo apt-get install texlive-publishers