IsIndefinite

Whether a QuadraticForm is indefinite: its discriminant is positive and not a perfect square.

IsIndefinite(form)$D>0$ and not a perfect square

Typed signatures

Type	Package	Applies
(expression<QuadraticForm>) -> boolean	modular	always

Domain: The modular group

Examples

Basic #

$D=5$ is positive and not a square

live ↗

In$\mathrm{IsIndefinite}(\mathrm{QuadraticForm}(1, 1, -1))$Out$\mathrm{True}$

$D=0$ is a perfect square

live ↗

In$\mathrm{IsIndefinite}(\mathrm{QuadraticForm}(1, 2, 1))$Out$\mathrm{False}$

About

Examples	2

See also: QuadraticForm, FormClassNumber