# cblas_sspr(_:_:_:_:_:_:_:) Rank one update: adds a packed symmetric matrix to the product of a scaling factor, a vector, and its transpose (single precision). ``` func cblas_sspr(_ ORDER: CBLAS_ORDER, _ UPLO: CBLAS_UPLO, _ N: __LAPACK_int, _ ALPHA: Float, _ X: UnsafePointer?, _ INCX: __LAPACK_int, _ AP: UnsafeMutablePointer?) ``` ## Parameters `ORDER` Specifies row-major (C) or column-major (Fortran) data ordering. `UPLO` Specifies whether to use the upper or lower triangle from the matrix. Valid values are `'U'` or `'L'`. `N` Order of matrix `A`; number of elements in vector `x`. `ALPHA` Scaling factor to multiply `x` by. `X` Vector `x`. `INCX` Stride within `X`. For example, if `incX` is 7, every 7th element is used. `AP` Matrix `A` (in packed storage format). ## Discussion Calculates `A + alpha*x*x` and stores the result in `A`. > 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. --- 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)