The FN package provides the functionality to represent a simple mathematical function such as an exponential, a polynomial or a rational function. This is used as a building block for defining the function associated to the nonlinear eigenproblem, as well as for specifying which function to use when computing the action of a matrix function on a vector.
| Beginner - Basic usage | FN | FNDestroy | FNType | 
| FNCreate | FNSetFromOptions | FNView | 
| Intermediate - Setting options for algorithms and data structures | FNCombineGetChildren | FNGetType | FNRationalSetDenominator | 
| FNCombineSetChildren | FNPhiGetIndex | FNRationalSetNumerator | 
| FNEvaluateDerivative | FNPhiSetIndex | FNSetScale | 
| FNEvaluateFunction | FNRationalGetDenominator | FNSetType | 
| FNGetScale | FNRationalGetNumerator | |
| Advanced - Setting more advanced options and customization | FNAppendOptionsPrefix | FNEvaluateFunctionMatVec | FNRegisterAll | 
| FNCombineType | FNGetOptionsPrefix | FNSetOptionsPrefix | 
| FNEvaluateFunctionMat | FNRegister | |
| Developer - Interfaces intended primarily for library developers, not for typical applications programmers | FNDuplicate | FNFinalizePackage | FNInitializePackage | 
| No deprecated routines | ||