---
title: "sparse_insert_block_float(_:_:_:_:_:_:)"
framework: accelerate
role: symbol
role_heading: Function
path: "accelerate/sparse_insert_block_float(_:_:_:_:_:_:)"
---

# sparse_insert_block_float(_:_:_:_:_:_:)

Inserts a dense block of entries into a single-precision matrix.

## Declaration

```swift
func sparse_insert_block_float(_ A: sparse_matrix_float!, _ val: UnsafePointer<Float>!, _ row_stride: sparse_dimension, _ col_stride: sparse_dimension, _ bi: sparse_index, _ bj: sparse_index) -> sparse_status
```

## Parameters

- `A`: The sparse matrix, A,_ _which must have been created with doc://com.apple.accelerate/documentation/Accelerate/sparse_matrix_block_create_float(_:_:_:_:) or doc://com.apple.accelerate/documentation/Accelerate/sparse_matrix_variable_block_create_float(_:_:_:_:). doc://com.apple.accelerate/documentation/Accelerate/SPARSE_ILLEGAL_PARAMETER is returned if not met. A holds block dimensions (fixed or variable) set with matrix object creation routine.
- `val`: Pointer to block to be inserted at block index location A[bi,bj]. The block is of dimension k * l where k and l are set for bi,bj at object creation time. The strides between elements for rows and columns are provided in row_stride and col_stride.
- `row_stride`: The row stride in number of elements to move from one row to the next for the block val.
- `col_stride`: The column stride in number of elements to move from one column to the next for the block val.
- `bi`: The block row index where val is to be inserted. Indexing is zero based, the first block is located at 0,0. Index is assumed to be within the bounds of the matrix object, undefined behavior if not met.
- `bj`: The block column index where val is to be inserted. Indexing is zero based, the first block is located at 0,0. Index is assumed to be within the bounds of the matrix object, undefined behavior if not met.

## Return Value

Return Value On successful insertion, A has been updated with the value and SPARSE_SUCCESS is returned. If A creation requirements are not met, SPARSE_ILLEGAL_PARAMETER is returned and A is unchanged.

## Discussion

Discussion Use to build a sparse matrix by providing a dense block for entry at block location A[bi,bj]. Block size is determined at object creation time. Given a block dimension of k * l and for location bi,bj, update as: A[bi,bj][i,j] = val[i*row_stride + j*col_stride] for each i in k and each j in l. Note that matrix properties cannot be modified after value insertion begins.This includes properties such as specifying a triangular matrix.Insertion can be expensive, generally speaking it is best to do a batch update. Inserted values may be temporarily held internally within the object and only inserted into the sparse format when a later computation triggers a need to insert. important: Apple provides the BLAS and LAPACK libraries under the Accelerate framework to be in line with LAPACK 3.9.1. Starting with iOS 26, iPadOS 26, macOS 26, tvOS 26, visionOS 26, and watchOS 26, the libraries are in line with LAPACK 3.12.0. These new interfaces provide additional functionality, as well as a new ILP64 interface. To use the new interfaces, define ACCELERATE_NEW_LAPACK before including the Accelerate or vecLib headers. For ILP64 interfaces, also define ACCELERATE_LAPACK_ILP64. For Swift projects, specify ACCELERATE_NEW_LAPACK=1 and ACCELERATE_LAPACK_ILP64=1 as preprocessor macros in Xcode build settings under Apple Clang - Preprocessing > Preprocessor Macros.

## See Also

### Matrix creation and population

- [sparse_matrix_block_create_double(_:_:_:_:)](accelerate/sparse_matrix_block_create_double(_:_:_:_:).md)
- [sparse_matrix_block_create_float(_:_:_:_:)](accelerate/sparse_matrix_block_create_float(_:_:_:_:).md)
- [sparse_matrix_variable_block_create_double(_:_:_:_:)](accelerate/sparse_matrix_variable_block_create_double(_:_:_:_:).md)
- [sparse_matrix_variable_block_create_float(_:_:_:_:)](accelerate/sparse_matrix_variable_block_create_float(_:_:_:_:).md)
- [sparse_insert_block_double(_:_:_:_:_:_:)](accelerate/sparse_insert_block_double(_:_:_:_:_:_:).md)
- [sparse_matrix_block_create_double_complex(_:_:_:_:)](accelerate/sparse_matrix_block_create_double_complex(_:_:_:_:).md)
- [sparse_matrix_block_create_float_complex(_:_:_:_:)](accelerate/sparse_matrix_block_create_float_complex(_:_:_:_:).md)