PDF Projection Software Module Design

PDF projection is inherently modular. Application of the chain-rule (Section 2.2.4) breaks down complex feature extraction processes into simple steps, each of which can be embodied by a module. This provides the opportunity for highly modularized software design. The following module functionalities are defined:

1. Feature extraction: calculating ${\bf z}=T({\bf x})$.
2. J-function calculation: calculating $J({\bf x}; H_0, T)=\frac{p({\bf x}\vert H_0)}{p({\bf z}\vert H_0)}$.
3. Inversion: computing a random sample ${\bf x}$ from the set ${\bf x}\in\{{\bf x}: T({\bf x})={\bf z}\}$, using uniform manifold sampling (UMS) (See Section 3.3).