https://github.com/sinshu/openblassharp
An OpenBLAS wrapper for .NET
https://github.com/sinshu/openblassharp
blas lapack linear-algebra math numerics openblas
Last synced: about 2 months ago
JSON representation
An OpenBLAS wrapper for .NET
- Host: GitHub
- URL: https://github.com/sinshu/openblassharp
- Owner: sinshu
- License: bsd-3-clause
- Created: 2024-01-21T06:06:49.000Z (over 1 year ago)
- Default Branch: main
- Last Pushed: 2025-01-13T03:33:55.000Z (5 months ago)
- Last Synced: 2025-03-23T13:38:28.643Z (2 months ago)
- Topics: blas, lapack, linear-algebra, math, numerics, openblas
- Language: C#
- Homepage:
- Size: 121 KB
- Stars: 5
- Watchers: 1
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- License: LICENSE.txt
Awesome Lists containing this project
README
# OpenBlasSharp
The purpose of this project is to provide a .NET wrapper for [OpenBLAS](https://github.com/OpenMathLib/OpenBLAS).
## Features
* Auto-generated thin wrapper for C# with no special marshalling.
* Covers BLAS, LAPACK, and OpenBLAS-specific functions.
* Most functions and arguments are annotated with doc comments taken from the original FORTRAN code.
This is very helpful when working with the BLAS and LAPACK functions, which often require a large number of arguments.
## Installation
[The NuGet package](https://www.nuget.org/packages/OpenBlasSharp) is available.
```ps1
Install-Package OpenBlasSharp
```
This package does not include the native binary.
[The `OpenBlasSharp.Windows` package](https://www.nuget.org/packages/OpenBlasSharp.Windows) provides the native binary for Windows.
```ps1
Install-Package OpenBlasSharp.Windows
```
Or, [download the compiled binary](https://github.com/OpenMathLib/OpenBLAS/releases) and put `libopenblas.dll` in the same directory as the executable file.
Binaries for both x86 and x64 architectures are supported, but [the ILP64 build with the `x64-64` suffix](https://github.com/OpenMathLib/OpenBLAS/blob/develop/docs/distributing.md#ilp64-interface-builds) is not supported.
All the classes are in the `OpenBlasSharp` namespace.
```cs
using OpenBlasSharp;
```
## BLAS Examples
BLAS functions are provided as static methods of the `Blas` class.
### Dot Product
```cs
var len = 3;
var rnd = new Random(42);
var x = Enumerable.Range(0, len).Select(i => rnd.NextDouble()).ToArray();
var y = Enumerable.Range(0, len).Select(i => rnd.NextDouble()).ToArray();
fixed (double* px = x)
fixed (double* py = y)
{
// Calculate x^T * y.
var result = Blas.Ddot(len, px, 1, py, 1);
}
```
### Matrix Multiplication
```cs
var m = 3;
var n = 5;
var k = 4;
var rnd = new Random(42);
var a = Enumerable.Range(0, m * k).Select(i => rnd.NextDouble()).ToArray();
var b = Enumerable.Range(0, k * n).Select(i => rnd.NextDouble()).ToArray();
var c = new double[m * n];
fixed (double* pa = a)
fixed (double* pb = b)
fixed (double* pc = c)
{
// Calculate c = a * b.
Blas.Dgemm(
Order.ColMajor,
Transpose.NoTrans,
Transpose.NoTrans,
m, n, k,
1.0,
pa, m,
pb, k,
0.0,
pc, m);
}
```
## LAPACK Examples
LAPACK functions are provided as static methods of the `Lapack` class.
### Inverse Matrix using LU Decomposition
```cs
var n = 3;
var random = new Random(42);
var a = Enumerable.Range(0, n * n).Select(i => random.NextDouble()).ToArray();
var piv = new int[n];
fixed (double* pa = a)
fixed (int* ppiv = piv)
{
Lapack.Dgetrf(
MatrixLayout.ColMajor,
n, n,
pa, n,
ppiv);
Lapack.Dgetri(
MatrixLayout.ColMajor,
n,
pa, n, // pa will be the inverse matrix.
ppiv);
}
```
### Singular Value Decomposition
```cs
var m = 4;
var n = 3;
var rnd = new Random(42);
var a = Enumerable.Range(0, m * n).Select(i => rnd.NextDouble()).ToArray();
var s = new double[Math.Min(m, n)];
var u = new double[m * m];
var vt = new double[n * n];
var work = new double[Math.Min(m, n) - 1];
fixed (double* pa = a)
fixed (double* ps = s)
fixed (double* pu = u)
fixed (double* pvt = vt)
fixed (double* pwork = work)
{
Lapack.Dgesvd(
MatrixLayout.ColMajor,
'A', 'A',
m, n,
pa, m, // Note that pa will be destroyed.
ps,
pu, m,
pvt, n,
pwork);
}
```
## OpenBLAS-specific functions
OpenBLAS-specific functions are provided as static methods of the `OpenBlas` class.
```cs
var numThreads = OpenBlas.GetNumThreads();
var numProcs = OpenBlas.GetNumProcs();
var config = OpenBlas.GetConfig();
```
## Limitations
* There are no plans to support low-level LAPACK functions with the `work` suffix.
* LAPACK functions that require function pointers are currently not supported, but support is planned for the future.
* The doc comments in the original FORTRAN code do not completely align with the C API of OpenBLAS, so the annotations for some APIs are incomplete.
## License
OpenBlasSharp is available under [the BSD-3-Clause license](LICENSE.txt).