Such as those converting to and from 'Double' in 'Field'. So far, they are seen in:

• (pretty) printing
• testing, e.g. 'eqNum' to account for margins of numerical error
• matrix related computations in those modules using HMatrix (note its replacement for Data.Matrix in branch WIP, but should still check for feasible component classes/types in the latter library)
• computing projections, due to 'sqrt', see 'project' in 'Simplex'
• computations involving 'factorial' and 'choose' in 'Combinatorics'

Initially, the existence of these class functions stemmed mostly from the numerics behind integration of polynomials and other computations of the like. Even though most practical uses of the library might involve ℝⁿ, it would be preferable to keep the classes neat and general.