office-42 — a word processor, a spreadsheet and a notebook, written from scratch in C

word42

A word processor.

A menu bar, two toolbars, a ruler, a status bar and a page. Styles, tables, footnotes, columns, headers and footers, mail merge, spelling, an outline view and a page-layout view that shows the paper it will be printed on.

word42 in page-layout view: a document with a title, headings, a bulleted list, a dropped capital and a table, on the page it will be printed on — word42 in page-layout view.

Reads and writes .docx, .doc, .odt, .rtf, HTML, Markdown and plain text.
Prints, and exports PDF with real text in it rather than a picture.
Undo for everything, and a document model that keeps what it was told.

Source on GitHub User guide Building it

office42

A spreadsheet.

A grid, a formula bar, a name box, two toolbars and sheet tabs. Five hundred and sixty-one functions, thirteen kinds of chart, pivot tables, the analysis tools, conditional formatting, form controls, and a recalculation that knows what depends on what.

office42 with a small sales sheet: a heading set in two fonts in one cell, a named cell style on the headings, currency and percent formats, a conditional format, a note, a text box and a three-dimensional column chart — office42 with a small sales sheet, a note, a text box and a 3-D chart.

Reads and writes .gnumeric, .xlsx, .xls, .ods, CSV and HTML; prints and exports PDF, and reads one back.
Python is the macro language — in a console, in =PY(), in functions of your own, and recorded from what you do.
A book can carry a whole SQLite database inside it, and =SQLVALUE() asks it from a cell.
office42-calc drives the same engine from a terminal.

Source on GitHub User guide How far it is from Excel Python The database

math42

A mathematics notebook.

Type an expression, press Enter, and the answer is set as mathematics: fractions stacked, powers raised, roots under a radical, matrices in brackets, graphs drawn. It speaks two languages — Sin[Pi/2] and sin(pi/2) both work.

math42: a notebook of input and output cells, with fractions, an integral, a matrix and a plot — math42, a page of a notebook.

Exact whole numbers and fractions, and whole numbers with no ceiling.
Calculus, linear algebra, statistics, differential equations and transforms — the mathematics an engineering degree teaches.
Notebooks are plain text, played back from the top, so a page is reproducible by construction.

Source on GitHub User guide

word42

office42

math42

The same principles, in all three