slepc-3.21.1 2024-04-26
Report Typos and Errors

## Spectral Transformation - ST

The Spectral Transformation (ST) class encapsulates the functionality required for acceleration techniques based on the transformation of the spectrum. As explained in the SLEPc Users Manual, the eigensolvers implemented in EPS work by applying an operator to a set of vectors and this operator can adopt different forms. The ST object handles all the different possibilities in a uniform way, so that the solver can proceed without knowing which transformation has been selected.

The type of spectral transformation can be specified at run time (e.g., `-st_type sinvert`) as well as several parameters such as the value of the shift (e.g., `-st_shift 1.5`).

Polynomial eigensolvers in PEP also support spectral transformation, see the users guide for details.

ST objects are always related to a solver object (either EPS or PEP). Users should not create a standalone ST object. ST options can also be set directly in application codes by first extracting the ST context from the EPS context via EPSGetST() and then directly calling the ST routines (e.g., STSetType() / STSetShift()).

Beginner - Basic usage
| ST | STSetFromOptions | STView
STCreate | STSetType |
STDestroy | STType |
Intermediate - Setting options for algorithms and data structures
| STCayleyGetAntishift | STFilterSetRange | STMatMode
STCayleySetAntishift | STGetKSP | STSetMatMode
STFilterGetDegree | STGetMatMode | STSetMatrices
STFilterGetInterval | STGetMatrix | STSetShift
STFilterGetRange | STGetNumMatrices | STViewFromOptions
STFilterSetDegree | STGetShift |
STFilterSetInterval | STGetType |
Advanced - Setting more advanced options and customization
| STAppendOptionsPrefix | STRegisterAll | STSetSplitPreconditioner
STGetMatStructure | STReset | STSetUp
STGetOperator | STRestoreOperator | STShellGetContext
STGetOptionsPrefix | STSHELL | STShellSetApply
STGetPreconditionerMat | STSetKSP | STShellSetApplyHermitianTranspose
STGetSplitPreconditionerInfo | STSetMatStructure | STShellSetApplyTranspose
STGetSplitPreconditionerTerm | STSetOptionsPrefix | STShellSetBackTransform
STRegister | STSetPreconditionerMat | STShellSetContext
Developer - Interfaces intended primarily for library developers, not for typical applications programmers
| STApply | STInitializePackage | STMatSolveHermitianTranspose
STApplyHermitianTranspose | STIsInjective | STMatSolveTranspose
STApplyMat | STMatCreateVecs | STPostSolve
STApplyTranspose | STMatCreateVecsEmpty | STPrecondGetKSPHasMat
STBackTransform | STMatGetLocalSize | STPrecondSetKSPHasMat
STCheckNullSpace | STMatGetSize | STResetMatrixState
STFilterGetThreshold | STMatMatSolve | STScaleShift
STFinalizePackage | STMatMult | STSetBalanceMatrix
STGetBalanceMatrix | STMatMultHermitianTranspose | STSetDefaultShift
STGetBilinearForm | STMatMultTranspose | STSetTransform
STGetMatrixTransformed | STMatSetUp | STSetWorkVecs
STGetTransform | STMatSolve |
No deprecated routines

Table of Contents