Gnumeric is the most powerful spreadsheet application which can import and export in various formats including csv, HTML, LaTeX, Lotus 1-2-3, OpenDocument Spreadsheet and Microsoft Excel.
Optional dependencies are(for Psion 5 file support), (for python plugin support) and (for viewing the help manual).
Gnumeric is depending on your locale and use it for exporting as csv file too. For example, octave use dot decimal seperator.
With german locale "de", Gnumeric shows 0,5 (comma)
With englisch locale "en", Gnumeric shows 0.5 (dot)
To start Gnumeric with a different locale, just run