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# cblas_cdotu_sub(_:_:_:_:_:_:)

Computes the dot product of two single-precision complex vectors.

```
func cblas_cdotu_sub(_ N: __LAPACK_int, _ X: OpaquePointer?, _ INCX: __LAPACK_int, _ Y: OpaquePointer?, _ INCY: __LAPACK_int, _ DOTU: OpaquePointer)
```

## Parameters

`N`

The length of vectors `X` and `Y`.

`X`

Vector `X`.

`INCX`

Stride within `X`. For example, if `incX` is 7, every 7th element is used.

`Y`

Vector `Y`.

`INCY`

Stride within `Y`. For example, if `incY` is 7, every 7th element is used.

`DOTU`

The result vector.

## 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.

---

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