Gnumeric

Gnumeric is a fiercely independent, deeply mathematical open-source veteran titan that mathematically attacked the "Statistical Inaccuracy" of commercial spreadsheets. Built for the GNOME desktop, it engineered an absolute masterclass in raw mathematical precision. It is the absolute weapon of choice for hardcore statisticians, scientists, and academics who mathematically demand an ultra-lightweight engine that calculates highly complex non-linear regression functions significantly more accurately than Microsoft Excel.