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
      Windows will complain about security risks and you have to keep the file anyway
      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 debian

      This package is for IT administrators.
      It will turn your debian 11 server as a gaiacalc server.
      The user will access gaiacalc web page with URL : http://yourservername.com
      
      First ensure that pip3 is installed (not included in debian11 on OVH cloud)
      Otherwise type this :
      sudo apt-get update
      sudo apt-get install python3-pip
      
      After downloading the file gaiacalc.deb, install it with command:
      sudo dpkg -i gaiacalc.deb
      That's it, nothing more is needed

      In order to deliver the gaiacalc.deb archive itself from your new server,
      you should copy or move it to /usr/local/lib/python3.9/dist-packages/gaiacalc/data
      
      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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