Spreadsheet::WriteExcel is a Perl module which can be used to create native Excel binary files. Formatted text and numbers can be written to multiple worksheets in a workbook. Formulas and functions are also supported. It is 100% Perl and doesn't require any Windows libraries or a copy of Excel. It will also work on the majority of Unix and Macintosh platforms. Generated files are compatible with Excel 97, 2000, 2002, and 2003, and with OpenOffice and Gnumeric. An older version also supports Excel 5/95.
Gnumeric is a powerful and easy to use spreadsheet using GNOME. Its goal is to provide a full featured spreadsheet and a smooth migration path for people and organizations currently using proprietary applications. It provides more sheet functions and greatly improved accuracy when compared to Microsoft's Excel. A plugin system lets you extend Gnumeric, adding functions, I/O formats, and real time data capabilities. The existing Python, Guile, and Perl plugins let you define complex functions. Gnumeric is capable of reading and writing MS Excel (XLS and Office Open XML), and reading Lotus, Applix, Quattro Pro, OpenCalc (ODF), XBase, DIF, SYLK, HTML, Psion, MPS, oleo, sc, misc. text formats, and its native XML. It can also generate Latex, HTML, and others.
Calligra is an integrated suite of applications that cover office, creative, and management needs. It offers applications on both desktop computers and mobile platforms like tablets and smartphones. OpenDocument Format (ODF) is used, making it compatible with OpenOffice.org, LibreOffice, and Microsoft Office. Calligra Suite contains the following applications: Calligra Words (word processor), Sheets (spreadsheets), Stage (presentations), Flow (diagrams and flowcharts), Kexi (visual database creator), Braindump (note taking), Plan (project management), Krita (drawing), and Karbon (vector graphics).
PLOTICUS is a command line utility for creating bar, line, pie, boxplot, scatterplot, sweep, heatmap, vector, timeline, Venn diagrams, and other types of charts and plots. ploticus is good for automated or just-in-time graph generation. It handles date, time, and categorical data nicely, and has some basic statistical capabilities. It can output to GIF, PNG, SVG, SWF, JPEG, PostScript, EPS, and X11. You can use convenient preset options or create complex scripts with rich and detailed color and style operations.
The GNOME Structured File Library is a utility library for reading and writing structured file formats. Support for MS OLE2 streams is complete, as is zip import. There is also support for document metadata and some initial work on decompressing VBA streams in OLE files for future conversion to other languages. This library replaces libole2 and is used in gnumeric, mrproject, abiword, libwv2, koffice. It is also part of the AAF format.
Siag Office is a free office package which consists of the spreadsheet Siag, the word processor PW, the animation program Egon, the text editor XedPlus, the file manager Xfiler and the previewer Gvu. Siag is easy to use, yet infinitely flexible through multiple embedded interpreters and a plugin mechanism that allows other programs to run inside the main document. The supported interpreters are SIOD, Guile, Tcl, and Python.
xlHtml converts an Excel spreadsheet file (.xls) into highly-optimized HTML. It includes scripts to allow it to be used as a Netscape or mutt plugin and as a xls handler for Apache. The program currently supports string, blank, boolean, error, integer, floating point, hyperlinks, and formula cells. It can also output in XML, tab delimited, or comma separated values (CSV).
QuantLib is a cross-platform, quantitative finance C++ library for modeling, pricing, trading, and risk management in real-life. It is also wrapped as Python/Ruby/Scheme modules. Extensions for Excel, R, and Mathematica are available. Other such extensions are under consideration. QuantLib offers tools that are useful both for practical implementation and for advanced modeling. It features market conventions, yield curve models, solvers, PDEs, Monte Carlo (low-discrepancy included), exotic options, VAR, and so on.