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

# sparse_get_block_dimension_for_col(_:_:)

Returns the dimension of the block for a specified column of a single-precision matrix.

## Declaration

```swift
func sparse_get_block_dimension_for_col(_ A: UnsafeMutableRawPointer!, _ j: sparse_index) -> Int
```

## Parameters

- `A`: The sparse matrix, A, which must have been created with doc://com.apple.accelerate/documentation/Accelerate/sparse_matrix_block_create_float(_:_:_:_:), doc://com.apple.accelerate/documentation/Accelerate/sparse_matrix_block_create_double(_:_:_:_:), doc://com.apple.accelerate/documentation/Accelerate/sparse_matrix_variable_block_create_float(_:_:_:_:), or doc://com.apple.accelerate/documentation/Accelerate/sparse_matrix_variable_block_create_double(_:_:_:_:). 0 is returned if not met. A holds block dimensions (fixed or variable) set with matrix object creation routine.
- `j`: The column to query.

## Return Value

Return Value The dimension of the block of the specified column.

## Discussion

Discussion 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

### Block dimension queries

- [sparse_get_block_dimension_for_row(_:_:)](accelerate/sparse_get_block_dimension_for_row(_:_:).md)