Install ISIS on Windows 10

Installing ISIS on Windows is not trivial but thanks to the available Linux subsystem in Windows 10 we can install it like any other Linux program. It is required that the WSL (Windows Subsystem Linux) is activated. Note that if you choose this way you have to compile isis. Using a singularity container will not work.

TL;DR

1. Enable WSL
   1. As Administrator start PowerShell (<WinKey> + R and type 'powershell' + <enter>)
   2. Enter dism.exe /online /enable-feature /featurename:VirtualMachinePlatform /all /norestart
   3. Restart your computer
2. Install Ubuntu WSL
   1. Open the Microsoft Store and search for 'Ubuntu'
   2. Install the latest Ubuntu version
   3. Start the newly installed Ubuntu System (this should provide you with a terminal) and complete the installation steps (enter user name and password)
3. Install required software
   1. In the newly installed Ubuntu environment type

      sudo apt install -y libreadline-dev libcurl4 libcurl4-gnutls-dev \
      libncurses*-dev xorg-dev build-essential gfortran perl-modules python-dev \
      pgplot5 libpng-dev libslang2-dev

      This will install all necessary tools to build and use heasoft and isis
   2. We strongly recommend to install s-lang before building isis. The best way to do this is by compiling it by yourself:

      wget https://www.jedsoft.org/releases/slang/slang-2.3.2.tar.bz2
      bzip2 -d slang-2.3.2.tar.bz2
      tar xvf slang-2.3.2.tar
      cd slang-2.3.2
      ./configure
      make
      make install
      ldconfig
      

      (alternatively, s-lang is also distributed via ubuntu, but this tends to older versions).

   3. Download the heasoft source from

      wget https://heasarc.gsfc.nasa.gov/FTP/software/lheasoft/lheasoft6.27/heasoft-6.27.2src.tar.gz

      Beware: The heasoft package is large and the connection slow so this make take up to several hours.

   4. Unpack the downloaded package with tar xvf heasoft-6.27.2src.tar.gz
   5. Enter the build directory

       cd heasoft-6.27.2/BUILD_DIR 

   6. Configure the package ...

       ./configure --prefix=$HOME/heasoft 

   7. ... build it ...

       make 

   8. ... and install

       make install 

4. Finally install ISIS
   1. Download ISIS: wget https://github.com/houckj/isis/archive/master.zip and unzip unzip master.zip
   2. Enter the directory cd isis-master
   3. Make heasoft known to the system

      export HEADAS=$HOME/heasoft/x86_64-pc-linux-gnu-libc2.27/
      source $HEADAS/headas-init.sh

      This step is required every time one wants to use ISIS
   4. Configure isis

      ./configure --with-headas=$HEADAS --with-cfitsio=$HEADAS --with-slang=/usr --with-pgplot=/usr --prefix=$HOME

   5. And finally

       make && make install 

      To install isis in $HOME/isis/1.6.2

Installing an X11 Server to use graphical applications

TL;DR

1. Install Xming from https://sourceforge.net/projects/xming/files/Xming/6.9.0.31/Xming-6-9-0-31-setup.exe/download
2. After Xming is successfully installed launch it and make it known to your linux environment

   export DISPLAY=localhost:0.0