Show HN: I made a spreadsheet where formulas also update backwards
2 days ago
- #spreadsheet
- #math
- #open-source
- Bidicalc allows changing formula outputs and automatically updating inputs, unlike traditional spreadsheets.
- Supports complex formulas including exponents, logarithms, trigonometric functions, and more.
- Users can toggle between editing a formula's expression or its numeric value.
- Handles multiple solutions by allowing users to set constants or reformulate problems.
- Features include keyboard shortcuts, text mode, and constant variables (prefixed with #).
- The solver uses a custom algorithm combining constraint propagation, Newton's method, and dichotomic search.
- Open-source under AGPL, with potential for future improvements like domain restrictions and solver enhancements.
- Current limitations include single precision in backward solver and UI thread computation blocking.
- Encourages community feedback and contributions via GitHub.