vector addition and pointwise scalar multiplication. These operations are defined by $$\left(\alpha\mathcal{G}_1 + \mathcal{G}_2\right)[t,f](A) = \alpha\left(\mathcal{G}_1[t,f](A)\right) + \mathcal{G}_2[t,f](A),$$ for $\alpha\in\mathbb{R}$ and $\mathcal{G}_1,\mathcal{G}_2 \in \mathcal{MF}_0$. A norm $||\mathcal{G}||$ provides a notion of absolute vector magnitude that can produce a distance metric $$d(\mathcal{G}_1,\mathcal{G}_2) = ||\mathcal{G}_1 - \mathcal{G}_2||.$$ One candidate for the norm is