sp_cgs

Use a conjugate gradient for a normal equation to solve the system A.x = b

# Calling Sequence

    [xsol[,iter]] = sp_cgne(A,b,tol[,maxit[,M[,x0]]])

## Parameters

A

- the A real sparse matrix of the system to be solved.

b

- the b real vector of the system to be solved.

tol

- the tolerance for the resolution of the equation system.

maxit

- the maximum number of iteration of the solver.

M

- the preconditionning matrix (an identity matrix by default). The preconditionning matrix must be symmetric.

x0

- an initial starting solution.

xsol

- the solution vector of the system.

iter

- the number of iterations performed to solve the system.

## Description

Use a conjugate gradient for a normal equation to solve the system A.x = b

## Example

## See Also

- sp_luinc
- sp_chol
- sp_cholinc
- sp_lu
- sp_cgs
- sp_gmres
- sp_mgcr
- sp_chsolve
- sp_lusolve

## Authors

- Yann COLLETTE