There are a number of fairly slavish emulations of Microsoft Excel and its commercial predecessors.
There are some "application platforms" that include spreadsheets.
There are other kinds of spreadsheets implemented to try out one or another interesting idea.
Spreadsheets that (more or less) predate Excel
For better or worse, the only ones that have really had much "uptake" are the "slavish emulations."
Notable Gnumeric features include:
Ability to import and export Excel files
100% of Excel functions
Import of CSV, WK1, xBase data formats
Printing via gnome-print, thus providing support for things like Type 1 anti-aliased fonts, which allows high quality display.
Various analysis tools including statistical functions and a "goal seek" tool
A Lotus 123 compatible character based spreadsheet. Once sold commercially, the binaries for Linux are freely redistributable.
OpenOffice.org™, formerly sold as StarOffice, has been released as Free Software .
The spreadsheet package is somewhat "interface independent;" it has both Xlib and Gtk versions; it is also reported to have an interface based on the CURSES library that can thus run on any sort of "dumb terminal."
The various modules are gradually attaining increasing interoperability with such data formats as:
RTF (Rich Text Format)
WKS (Lotus 123's data format)
As the packages are extendible using Scheme, there is almost nothing that they cannot, at least in concept, do.
For those wishing to be on the bleeding edge, the latest and
most unstable sources for Siag are now
available through anonymous CVS. Set
then execute: cvs login, and cvs checkout
Development has not been real active lately; it appears that some developers have migrated to working on Gnumeric.
Recent claims to fame include:
An interpretive Java spreadsheet utilizing Java spec syntax.
Portable to any reasonably Unix-like OS; written in C. Uses a somewhat functional model. It can read Lotus 123 WKS files.
This is a spreadsheet implemented in C/C++, which is extendable using TCL.
A spreadsheet package implemented in Objective C available under a BSD style license, presently running only on MacOS, inspired by Quantrix.
This hasn't been changed much since 2004, when the source code was released; it does, nonetheless, work, on MacOS, and gives a good idea as to how Improv worked, combining the notions of building spreadsheets as multidimensional tables, and formulae that control ranges of cells
A web application that lets you easily extract tabular data from PDF files.
It's actually not nearly so "easily" as one might hope; the process of "cooking" data into PDF removes a lot that would be useful in getting it back into usable text.
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