OpenOffice.org 3.x is the leading open-source open software suite for word processing, spreadsheets, presentations, openoffice_logographics, databases and more. You can adjust openoffice to your needs by adding more functionality with the help of extensions. Find bellow five useful extensions for openoffice with installation guide.
2- Convert Text To Number (and date)
ConvertTextToNumber replaces numbers and dates, formatted as text, with real numbers.
Choices can be made about marking of cells, including cells with non- default decimal separators, conversion of dates, and more.
As a result of the conversion, the text cells will become real numbers, and then will be counted in formulas Calc.
Calc does not use numbers formatted as text. Other spreadsheet programs may well do that in certain circumstances.
This extension adds the tool bar 'CT2N' to Calc only. The screen shot shows it all.
3- accentuate