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# BLAS_THREADING

Constants that describe the BLAS and LAPACK threading model.

```
struct BLAS_THREADING
```

## Overview

Use the threading model constants to specify whether BLAS and LAPACK operations run in a single thread or multiple threads. Specify the single-threaded model if your app uses its own threading mechanism.

## Topics

### Raw values

### Specifying a threading model

[`init(_:)`](/documentation/Accelerate/BLAS_THREADING/init(_:))

Creates a threading model constant.

[`init(rawValue:)`](/documentation/Accelerate/BLAS_THREADING/init(rawValue:))

Creates a threading model constant with an unsigned-integer value.

[`rawValue`](/documentation/Accelerate/BLAS_THREADING/rawValue)

The raw value that represents the threading model.

[`BLAS_THREADING_MULTI_THREADED`](/documentation/Accelerate/BLAS_THREADING_MULTI_THREADED)

A constant that specifies that the Accelerate framework decides whether BLAS and LAPACK execute on single or multiple threads.

[`BLAS_THREADING_SINGLE_THREADED`](/documentation/Accelerate/BLAS_THREADING_SINGLE_THREADED)

A constant that specifies BLAS and LAPACK execute on a single thread only.

[`BLAS_THREADING_MAX_OPTIONS`](/documentation/Accelerate/BLAS_THREADING_MAX_OPTIONS)


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