Gaiacalc Installation instructions
      
      You have 5 options :
      
      - Download MacOS application
      - Download Windows exe file
      - Install a python package with the classical pip tool
      - Install a linux debian package to build a gaiacalc server
      - Get the source code on GitHub
			  
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      Download app for MacOS

      You will get the file gaiacalc.dmg.
      This is a virtual disk including the app.
      
      Installation:
      - double click gaiacalc.dmg
      - you get a new disk in your finder window, click on it
      - you have a single element inside : gaiacalc.app
      - you can drag and drop it into your Applications folder, or anywhere you want
      - you have to allow MacOS to run the app downloaded from internet
      - ctrl-click the gaiacalc icon to get the contextual menu
      - choose the "open" item
      - you get a window with a security warning
      - now click the "Open" button
      - first launching may be quite long, give it some time (seconds, not minutes :)
      
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      Download exe for Windows

      You will get the file gaiacalc.exe
      Double click to open gaiacalc
      First launching may be quite long, give it some time (seconds, not minutes :)
      
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      Download pip package for python

      You can install gaiacalc as a python3 package
      
      On MacOS, use a terminal and type this command line:
      python3 -m pip install gaiacalc
      Then you get a gaiacalc command : type "gaiacalc" then RETURN key
      
      On Windows, use a cmd window and type this:
      py -m pip install gaiacalc
      Then you get a gaiacalc command : type "gaiacalc" then RETURN key
      
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      Download deb package for linux deban

      Not yet available
      This package is for IT administrators.
      It will turn your debian server as a gaiacalc server.
      The user will access gaiacalc web page with URL : http://yourservername.com
      
      After downloading the file gaiacalc.deb, install it with command:
      sudo dpkg -i gaiacalc.deb
      That's it, nothing more is needed
      
      If you want to change the server port, you can edit file /etc/init.d/gaiacalc
      Find there the args --tcpport in the line DAEMON_ARGS.
      You can change the value 80 to 8080 for example.
      Save the change and reboot your server with command : sudo reboot
      Users will now access to http://yourservername.com:8080
      
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      Download source code

      Everything you need to build and use all versions :
      code, packaging doc, technical doc

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