# init(structure:data:) Creates a sparse matrix with the specified structure that contains double-precision values. ``` init(structure: SparseMatrixStructure, data: UnsafeMutablePointer) ``` ## Parameters `structure` The sparsity structure of the matrix. `data` The array of contiguous values in the nonzero blocks of the matrix. The matrix stores each block in column-major order. The number of elements in [`data`](/documentation/Accelerate/SparseMatrix_Double/data) must be equal to [`blockSize`](/documentation/Accelerate/SparseMatrixStructure/blockSize) x [`blockSize`](/documentation/Accelerate/SparseMatrixStructure/blockSize) x the number of nonzero blocks in the matrix. --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)