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# Subfactor Functions

Extract and work with subfactors.

## Topics

### Subfactor Extraction

[`struct SparseSubfactor_t`](/documentation/Accelerate/SparseSubfactor_t)

Constants that define the subfactor of a factorization.

[`func SparseCreateSubfactor(SparseSubfactor_t, SparseOpaqueFactorization_Double) -> SparseOpaqueSubfactor_Double`](/documentation/Accelerate/SparseCreateSubfactor(_:_:)-49d8w)

Returns an opaque object that represents a subfactor of a factorization of a matrix of double-precision values.

[`struct SparseOpaqueFactorization_Double`](/documentation/Accelerate/SparseOpaqueFactorization_Double)

A structure that represents the factorization of a matrix of double-precision, floating-point values.

[`func SparseCreateSubfactor(SparseSubfactor_t, SparseOpaqueFactorization_Float) -> SparseOpaqueSubfactor_Float`](/documentation/Accelerate/SparseCreateSubfactor(_:_:)-4renf)

Returns an opaque object that represents a subfactor of a factorization of a matrix of single-precision values.

[`struct SparseOpaqueFactorization_Float`](/documentation/Accelerate/SparseOpaqueFactorization_Float)

A structure that represents the factorization of a matrix of single-precision, floating-point values.

[`func SparseCreateSubfactor(SparseSubfactor_t, SparseOpaqueFactorization_Complex_Double) -> SparseOpaqueSubfactor_Complex_Double`](/documentation/Accelerate/SparseCreateSubfactor(_:_:)-39487)

Returns an opaque object representing a sub-factor of a
factorization in complex double.

[`func SparseCreateSubfactor(SparseSubfactor_t, SparseOpaqueFactorization_Complex_Float) -> SparseOpaqueSubfactor_Complex_Float`](/documentation/Accelerate/SparseCreateSubfactor(_:_:)-udwd)

Returns an opaque object representing a sub-factor of a
factorization in complex float.

### Structures

[`struct SparseOpaqueSubfactor_Double`](/documentation/Accelerate/SparseOpaqueSubfactor_Double)

Represents a sub-factor of the factorization (for example,  `L` from `LDL^T`).

[`struct SparseOpaqueSubfactor_Float`](/documentation/Accelerate/SparseOpaqueSubfactor_Float)

Represents a sub-factor of the factorization (for example,  `L` from `LDL^T`).

[`struct SparseOpaqueSubfactor_Complex_Double`](/documentation/Accelerate/SparseOpaqueSubfactor_Complex_Double)

Represents a sub-factor of the factorization (for example,  `L` from `LDL^T`).

[`struct SparseOpaqueSubfactor_Complex_Float`](/documentation/Accelerate/SparseOpaqueSubfactor_Complex_Float)

Represents a sub-factor of the factorization (for example,  `L` from `LDL^T`).

### Subfactor Solve and Operation Functions

  <doc://com.apple.accelerate/documentation/Accelerate/subfactor-solve-functions>

  <doc://com.apple.accelerate/documentation/Accelerate/subfactor-multiplication-functions>


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