public static void Normal(float loc, float scale, NdArray @out)
{
FunctionHandle funcHandle;
NativeMethods.MXGetFunction("_sample_normal", out funcHandle);
var input = IntPtr.Zero;
var output = @out.Handle;
var paramKeys = new string[] { "loc", "scale", "shape" };
var paramVals = new string[]
{
loc.ToString(),
scale.ToString(),
@out.GetShape().ToString()
};
Util.CallCheck(NativeMethods.MXFuncInvokeEx(
funcHandle,
ref input,
new float[0],
ref output,
paramKeys.Length,
paramKeys,
paramVals
));
}
public static void Uniform(float low, float high, NdArray @out)
{
FunctionHandle funcHandle;
NativeMethods.MXGetFunction("_sample_uniform", out funcHandle);
var input = IntPtr.Zero;
var output = @out.Handle;
var paramKeys = new string[] { "low", "high", "shape" };
var paramVals = new string[]
{
low.ToString(CultureInfo.InvariantCulture),
high.ToString(CultureInfo.InvariantCulture),
@out.GetShape().ToString()
};
Util.CallCheck(NativeMethods.MXFuncInvokeEx(
funcHandle,
ref input,
new float[0],
ref output,
paramKeys.Length,
paramKeys,
paramVals
));
}
public override NdArray create_state(int index, NdArray weight)
{
if (Math.Abs(this._momentum) < float.Epsilon)
{
return(null);
}
return(NdArray.Zeros(weight.GetShape(), weight.GetContext(), weight.GetDtype()));
}
protected override void InitWeight(string name, NdArray arr)
{
var shape = arr.GetShape();
float hwScale = 1.0f;
if (shape.Size() > 2)
{
hwScale = Util.Prod(shape.Data().Skip(2).ToArray());
}
var fanOut = shape[0] * hwScale;
var fanIn = shape[1] * hwScale;
float factor = 1.0f;
switch (_factorType)
{
case FactorType.Avg:
factor = (fanIn + fanOut) / 2.0f;
break;
case FactorType.In:
factor = fanIn;
break;
case FactorType.Out:
factor = fanOut;
break;
default:
throw new ArgumentOutOfRangeException(nameof(FactorType));
}
var scale = (float)Math.Sqrt(this._magnitude / factor);
switch (_rndType)
{
case RndType.Uniform:
Random.Uniform(-scale, scale, arr);
break;
case RndType.Gaussian:
Random.Normal(-scale, scale, arr);
break;
default:
throw new ArgumentOutOfRangeException(nameof(RndType));
}
}
protected virtual void InitBilinear(string name, NdArray arr)
{
var shape = arr.GetShape().Data();
var prodShape = Util.Prod(shape);
float[] weight = new float[prodShape];
var f = Math.Ceiling(shape[3] / 2.0);
var c = (2 * f - 1 - f % 2) / (2.0 * f);
for (int i = 0; i < prodShape; i++)
{
var x = i % shape[3];
var y = (i / shape[3]) % shape[2];
weight[i] = (float)((1 - Math.Abs(x / f - c)) * (1 - Math.Abs(y / f - c)));
}
arr.SyncCopyFromCpu(weight);
}
protected virtual void InitLocBias(string name, NdArray arr)
{
Util.Assert(arr.GetShape()[0] == 6);
arr.SyncCopyFromCpu(new[] { 1.0f, 0, 0, 0, 1.0f, 0 });
}
