public static void SdcaL1UpdateSparse(float primalUpdate, int count, ReadOnlySpan <float> source, ReadOnlySpan <int> indices, float threshold, Span <float> v, Span <float> w)
{
Contracts.AssertNonEmpty(source);
Contracts.AssertNonEmpty(indices);
Contracts.AssertNonEmpty(v);
Contracts.AssertNonEmpty(w);
Contracts.Assert(count > 0);
Contracts.Assert(count <= source.Length);
Contracts.Assert(count <= indices.Length);
Contracts.Assert(count <= v.Length);
Contracts.Assert(count <= w.Length);
if (Avx.IsSupported)
{
AvxIntrinsics.SdcaL1UpdateSU(primalUpdate, count, source, indices, threshold, v, w);
}
else if (Sse.IsSupported)
{
SseIntrinsics.SdcaL1UpdateSU(primalUpdate, count, source, indices, threshold, v, w);
}
else
{
for (int i = 0; i < count; i++)
{
int index = indices[i];
v[index] += source[i] * primalUpdate;
float value = v[index];
w[index] = Math.Abs(value) > threshold ? (value > 0 ? value - threshold : value + threshold) : 0;
}
}
}
private static void SdcaL1UpdateSparse(float primalUpdate, Span <float> src, Span <int> indices, float threshold, Span <float> v, Span <float> w)
{
if (Sse.IsSupported)
{
SseIntrinsics.SdcaL1UpdateSU(primalUpdate, src, indices, threshold, v, w);
}
else
{
for (int i = 0; i < indices.Length; i++)
{
int index = indices[i];
v[index] += src[i] * primalUpdate;
float value = v[index];
w[index] = Math.Abs(value) > threshold ? (value > 0 ? value - threshold : value + threshold) : 0;
}
}
}