static void Main(string[] args)
{
// Based on http://brahma.codeplex.com/SourceControl/latest#trunk/Source/Samples/OpenCL/FastFourierTransform/Program.cs
int size = 8388608;
// Input Data
Random random = new Random();
var input = Enumerable.Range(1, size).Select(x => new Complex {
A = (float)random.NextDouble(), B = 0.0f
}).ToArray();
var output = Enumerable.Range(1, size).Select(x => new Complex {
A = 0.0f, B = 0.0f
}).ToArray();
var xs = Enumerable.Range(0, size - 1).ToArray();
using (var context = new GpuContext())
{
using (var _xs = context.CreateGpuArray(xs))
{
var _input = context.CreateGpuArray(input);
var _output = context.CreateGpuArray(output);
// Forward FFT
int fftSize = 2;
for (int i = 0; i < System.Math.Log(size, 2.0); i++)
{
var query = (from x in _xs.AsGpuQueryExpr()
let b = (((int)FMath.Floor((float)x / fftSize)) * (fftSize / 2))
let offset = x % (fftSize / 2)
let x0 = b + offset
let x1 = x0 + size / 2
let val0 = _input[x0]
let val1 = _input[x1]
let angle = -2 * FMath.PI * (x / fftSize)
let t = new Complex {
A = FMath.Cos(angle), B = FMath.Sin(angle)
}
select new Complex
{
A = val0.A + t.A * val1.A - t.B * val1.B,
B = val0.B + t.B * val1.A + t.A * val1.B
});
fftSize *= 2;
context.Fill(query, _output);
Swap(ref _input, ref _output);
}
}
}
}
public void MathFunctionsSingle()
{
using (var context = new GpuContext(platformWildCard))
{
Spec.ForAny <int[]>(xs =>
{
using (var _xs = context.CreateGpuArray(xs))
{
var gpuResult = context.Run((from n in _xs.AsGpuQueryExpr()
let pi = SMath.PI
let c = SMath.Cos(n)
let s = SMath.Sin(n)
let f = SMath.Floor(pi)
let sq = SMath.Sqrt(n * n)
let ex = SMath.Exp(pi)
let p = SMath.Pow(pi, 2)
let a = SMath.Abs(c)
let l = SMath.Log(n)
select f *pi *c *s *sq *ex *p *a *l).ToArray());
var openClResult = this.MathFunctionsSingleTest(xs);
return(gpuResult.Zip(openClResult, (x, y) => (float.IsNaN(x) && float.IsNaN(y)) ? true : System.Math.Abs(x - y) < 0.001)
.SequenceEqual(Enumerable.Range(1, xs.Length).Select(_ => true)));
}
}).QuickCheckThrowOnFailure();
}
}
