---
title: "SparseMultiply(_:_:_:)"
framework: accelerate
role: symbol
role_heading: Function
path: "accelerate/sparsemultiply(_:_:_:)-20xvs"
---

# SparseMultiply(_:_:_:)

Performs the multiply operation Y = Subfactor * X, in place on a dense matrix of double-precision values and without any internal memory allocations.

## Declaration

```swift
func SparseMultiply(_ Subfactor: SparseOpaqueSubfactor_Double, _ XY: DenseMatrix_Double, _ workspace: UnsafeMutableRawPointer)
```

## Parameters

- `Subfactor`: The subfactor to multiply by, which doc://com.apple.accelerate/documentation/Accelerate/SparseCreateSubfactor(_:_:)-49d8w returns
- `XY`: On input, the matrix X. On return, the matrix Y overwrites it.
- `workspace`: A workspace of size workspaceRequiredStatic + nrhs * workspaceRequiredPerRHS where nrhs is the number of right-hand-side vectors.

## See Also

### Subfactor and dense matrix multiplication with user-defined workspace

- [SparseMultiply(_:_:_:)](accelerate/sparsemultiply(_:_:_:)-6thvw.md)
- [SparseMultiply(_:_:_:_:)](accelerate/sparsemultiply(_:_:_:_:)-2osop.md)
- [SparseMultiply(_:_:_:_:)](accelerate/sparsemultiply(_:_:_:_:)-9v8hk.md)
- [SparseMultiply(_:_:_:)](accelerate/sparsemultiply(_:_:_:)-6strd.md)
- [SparseMultiply(_:_:_:)](accelerate/sparsemultiply(_:_:_:)-7mdi8.md)
- [SparseMultiply(_:_:_:_:)](accelerate/sparsemultiply(_:_:_:_:)-581zl.md)