linux

• GNU Parallel
  • Running Parallel on HPCs
  • Parallel Umbrella Sampling Windows for MD Simulations
• awk - manipulate text
  • Separator
  • awk can do math.
• cat - print input to standard output
• cd - change directories
• chsh - change shell
• cp - copy files or folders
• echo - Print Argument
• grep - search for pattern in file or folders
• head - read from top of file to standard output
• help - read documentation
• less - view files
• ls - list information about files/folders
• man - documentation for various functions
• mkdir - make new directories.
• module - load software on slurm
• mv - move files/folders from one place to another.
• pwd - print working directory
• rm - delete files
• rsync - sync files/folders
• sbatch - Submit job to Slurm
• scancel - Cancel Slurm Jobs
• scp - copy files/folders over ssh
• sed - tranform/replace text!
• seq - sequence of numbers
• setfacl - change file/folder permissions
• sinfo - View information about Slurm nodes and partitions.
  • Find idle partitions
• sort - sorts lines
• ssh - secure shell protocol
• ssh-keygen - Make SSH key
• tail - read from bottom of file
• tar - compress/uncompress files
• touch - Make File
• trap - signalled execution

Reset GNOME Terminal Hotkeys

dconf reset -f /org/gnome/terminal/legacy/keybindings/

Manging Multiple Compiler Versions

• for personal machines

For example, if you need multiple versions of gcc/g++ on a single machine running Ubuntu 22.04

• First install with sudo apt-get

sudo apt-get install gcc-11 gcc-10 gcc-9 g++-11 g++-10 g++-9 -y

• Use the updalternativesate to create list of multiple gcc and g++ compiler alternatives

• Larger number = higher priority

  • here, gcc and g++ 11 is default

sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-9 0
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-9 0
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-10 1
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-10 1
sudo update-alternatives --install /usr/bin/gcc gcc /usr/bin/gcc-11 2
sudo update-alternatives --install /usr/bin/g++ g++ /usr/bin/g++-11 2

• Check the available c and c++ compilers list on your system and select desired version by entering relevant selection number:

sudo update-alternatives --config gcc
sudo update-alternatives --config g++

• Sanity check

gcc --version
g++ --version