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# SparseFactorization_t

Constants that define the factorization type.

```
struct SparseFactorization_t
```

## Topics

### LU factorization types

[`SparseFactorizationLU`](/documentation/Accelerate/SparseFactorizationLU)

Default LU factorization, currently LU with TPP.

[`SparseFactorizationLUSPP`](/documentation/Accelerate/SparseFactorizationLUSPP)

LU factorization with partial pivoting restricted to within supernodes only.

[`SparseFactorizationLUTPP`](/documentation/Accelerate/SparseFactorizationLUTPP)

LU factorization with threshold partial pivoting.

[`SparseFactorizationLUUnpivoted`](/documentation/Accelerate/SparseFactorizationLUUnpivoted)

LU factorization with no numerical pivoting.

### Factorization types for symmetric coefficient matrices

[`SparseFactorizationCholesky`](/documentation/Accelerate/SparseFactorizationCholesky)

A constant that represents Cholesky (*LLᵀ*) factorization.

[`SparseFactorizationLDLT`](/documentation/Accelerate/SparseFactorizationLDLT)

A constant that represents the default *LDLᵀ* factorization.

[`SparseFactorizationLDLTUnpivoted`](/documentation/Accelerate/SparseFactorizationLDLTUnpivoted)

A constant that represents Cholesky-like *LDLᵀ* factorization with only one-by-one pivots and no pivoting.

[`SparseFactorizationLDLTSBK`](/documentation/Accelerate/SparseFactorizationLDLTSBK)

A constant that represents *LDLᵀ* factorization with Supernode-Bunch-Kaufman and static pivoting.

[`SparseFactorizationLDLTTPP`](/documentation/Accelerate/SparseFactorizationLDLTTPP)

A constant that represents *LDLᵀ* factorization with full-threshold partial pivoting.

### Factorization types for overdetermined and underdetermined systems

[`SparseFactorizationQR`](/documentation/Accelerate/SparseFactorizationQR)

A constant that represents QR factorization.

[`SparseFactorizationCholeskyAtA`](/documentation/Accelerate/SparseFactorizationCholeskyAtA)

A constant that represents *QR* factorization without storing *Q*.

### Raw Values

[`init(_:)`](/documentation/Accelerate/SparseFactorization_t/init(_:))

[`init(rawValue:)`](/documentation/Accelerate/SparseFactorization_t/init(rawValue:))

[`rawValue`](/documentation/Accelerate/SparseFactorization_t/rawValue)

## Relationships

### Conforms To

[`Sendable`](/documentation/Swift/Sendable)

[`Equatable`](/documentation/Swift/Equatable)

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Hashable`](/documentation/Swift/Hashable)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

---

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