hifir4py.ksp.GMRES_WorkSpace

class GMRES_WorkSpace(n: int, restart: int = 30, dtype: numpy.dtype = <class 'numpy.float64'>)

Workspace class for GMRES solver

This class is a collection of all buffer arrays used in GMRES solver, i.e., gmres_hif. Users can create this buffer object a priori, so that it will be efficient to invoke GMRES multiple times.

y

Length of restart+1

Type:ndarray

R

restart-restart upper triangular matrix used in Arnoldi

Type:ndarray

Q

restart-n used in Arnoldi

Type:ndarray

J

2-restart used in Given’s rotation

Type:ndarray

v, w

Length-n arrays

Type:ndarray

w2

Length of restart

Type:ndarray

Examples

The following code constructs a workspace buffer that is length 10 and with restart dimension 30.

>>> from hifir4py.ksp import *
>>> work = GMRES_WorkSpace(10)

__init__(n: int, restart: int = 30, dtype: numpy.dtype = <class 'numpy.float64'>)

Constructor of workspace buffer for GMRES

Parameters:

• n (int) – Length of the RHS vector
• restart (int, optional) – Restart dimension of KSP, default is 30
• dtype (dtype) – Data type, default is double-precision real

property dtype: numpy.dtype

NumPy data type

Type:numpy.dtype

property restart: int

Restart dimension

Type:int

property size: int

Size (length) of the workspace

Type:int