---
title: SparseGMRESOptions
framework: accelerate
role: symbol
role_heading: Structure
path: accelerate/sparsegmresoptions
---

# SparseGMRESOptions

Options for creating a generalized minimal residual (GMRES) method.

## Declaration

```swift
struct SparseGMRESOptions
```

## Overview

Overview Use GMRES to solve Ax = b when A is symmetric indefinite or unsymmetric. For symmetric positive-definite systems, use SparseConjugateGradient(_:). For rectangular or singular systems, use SparseLSMR(_:).

## Topics

### Initializers

- [init()](accelerate/sparsegmresoptions/init().md)
- [init(reportError:variant:nvec:maxIterations:atol:rtol:reportStatus:)](accelerate/sparsegmresoptions/init(reporterror:variant:nvec:maxiterations:atol:rtol:reportstatus:).md)

### Inspecting GMRES Options

- [atol](accelerate/sparsegmresoptions/atol.md)
- [maxIterations](accelerate/sparsegmresoptions/maxiterations.md)
- [nvec](accelerate/sparsegmresoptions/nvec.md)
- [reportError](accelerate/sparsegmresoptions/reporterror.md)
- [reportStatus](accelerate/sparsegmresoptions/reportstatus.md)
- [rtol](accelerate/sparsegmresoptions/rtol.md)
- [variant](accelerate/sparsegmresoptions/variant.md)
- [SparseGMRESVariant_t](accelerate/sparsegmresvariant_t.md)

## Relationships

### Conforms To

- [BitwiseCopyable](swift/bitwisecopyable.md)
- [Sendable](swift/sendable.md)

## See Also

### Sparse Iterative Methods for Symmetric Indefinite and Unsymmetric Coefficient Matrices

- [SparseGMRES()](accelerate/sparsegmres().md)
- [SparseGMRES(_:)](accelerate/sparsegmres(_:).md)