# SuanShu, a Java numerical and statistical library

com.numericalmethod.suanshu.algebra.linear.matrix.doubles.matrixtype.sparse.solver.iterative.preconditioner

## Interface Preconditioner

• ### Method Summary

All Methods
Modifier and Type Method and Description
Vector solve(Vector x)
Solve Mv = x, where M is the preconditioner matrix.
Vector transposeSolve(Vector x)
Solve Mtv = x, where M is the preconditioner matrix.
• ### Method Detail

• #### solve

Vector solve(Vector x)
Solve Mv = x, where M is the preconditioner matrix. In effect, this method returns v as the product M-1x.
Parameters:
x - a vector
Returns:
M-1x
• #### transposeSolve

Vector transposeSolve(Vector x)
Solve Mtv = x, where M is the preconditioner matrix. In effect, this method returns v as the product M-tx. This method is usually called by a solver which solves a dual system Atx* = b*. BiconjugateGradientSolver is an example of such a solver.
Parameters:
x - a vector
Returns:
M-tx