This library contains two robust functions to solve depressed and general cases of quartic equations with the use of Lodovico Ferrari's algorithm. The library depends on the lightweight suopte Complex class, which is also included in the repository.
Working on the StellaSphaera project I bumped into a geometric problem which involved the solution of a quartic equation. After long hesitation I decided to take a deep breath and dive into the world of complex numbers and quartic equations. Because I couldn't find any complex number class except the compliant and very readable but pretty cumbersome PEAR library - I found it better to create my own (suopte Complex). Then I started my journey in Lodovico Ferrari's labyrinth. Eventually with the guidance of the great Renaissance mathematician I easily got out of the maze.