isIsotropic -- determines whether a Grothendieck-Witt class is isotropic

• Usage:

  isIsotropic beta

• Inputs:
  • beta, a Grothendieck-Witt Class, denoted by $\beta\in\text{GW}(k)$, where $k$ is $\mathbb{C}$, $\mathbb{R}$, $\mathbb{Q}$, or a finite field of characteristic not 2
• Outputs:
  • a Boolean value, whether $\beta$ is isotropic