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# SparseOpaqueSubfactor_Double

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

```
struct SparseOpaqueSubfactor_Double
```

## Overview

- `attributes` :
  Attributes of subfactor. Notably transpose indicates whether it should be
  considered as the transpose of its underlying contents (e.g. should it
  count as L or L^T if `.contents=SparseSubfactorL`).
- `contents` :
  Subfactor this represents, e.g. L or Q.
- `factor` :
  Underlying factorization this subfactor is part of.
- `workspaceRequiredStatic` :
  The size of the workspace, in bytes, required to perform `SparseMultiply`
  or `SparseSolve` with this subfactor is given by the expression:
  `workspaceRequiredStatic + nrhs*workspaceRequiredPerRhs`
  where `nrhs` is the number of right-hand side vectors.
- `workspaceRequiredPerRHS` :
  The size of the workspace, in bytes, required to perform SparseMultiply()
  or SparseSolve() with this subfactor is given by the expression:
  workspaceRequiredStatic + nrhs*workspaceRequiredPerRhs
  where nrhs is the number of right-hand side vectors.

---

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