On 2D Inverse Problems/Notation

$\mathbb {N} {\mbox{ of natural numbers}}$

$\mathbb {D} {\mbox{ is the open disc domain}}$

$\mathbb {b} {\mbox{ is the open domain nature boundary}}$

$\mathbb {C} ^{\pm }{\mbox{ is the complex half-plane}}$

$mega{\mbox{ is a root of unity}}$

$\nabla {\mbox{ is the gradient}}$

$\Delta =\nabla \cdot \nabla {\mbox{ is the Laplace operator}}$

$\Lambda {\mbox{ is Dirichlet-to-Neumann operator}}$

$D_{x}{\mbox{ is a diagonal matrix w/the vector }}x{\mbox{ on the diagonal }}(D_{x}1=x)$

$D_{A}{\mbox{ is the diagonal matrix, coinciding on diagonal w/the matrix }}A$

$y,\lambda {\mbox{ is eigenvalue of operator/matrix}}$

$ma(A){\mbox{ is spectrum of matrix }}A,{\mbox{ zeros of characteristic polynomial }}$

$\rho (A){\mbox{ is the characteristic polynomial of matrix }}A$

$\tau {\mbox{ is the Cayley transform}}$

$ega{\mbox{ is a continuous domain}}$

$G/G^{*}{\mbox{ is graph or network and its dual}}$

$V_{G}{\mbox{ is the set of vertices of a graph}}$

$E_{G}{\mbox{ is the set of edges of a graph}}$

$M_{G}{\mbox{ is the medial graph of an embedded graph }}G$

$c{\mbox{ is conductivity}}$