C.Function get_length_and_remove_last_dimension(C.Function x, string name)
{
var number_dimensions = x.Output.Shape.Dimensions.Count;
x = CC.Square(x);
var sum_entries = CC.ReduceSum(x, new C.Axis(number_dimensions - 1));
var epsilon = C.Constant.Scalar(C.DataType.Float, 1e-7, computeDevice);
x = CC.Sqrt(CC.Plus(sum_entries, epsilon));
x = CC.Squeeze(x);
return(x);
}
C.Function create_capsule_layer(C.Function inputs, int num_capsule, int dim_capsule, int routings, string name)
{
var inputs_shape = inputs.Output.Shape.Dimensions;
var input_num_capsule = inputs_shape[0];
var input_dim_capsule = inputs_shape[1];
var W = new C.Parameter(
new int[] { num_capsule, dim_capsule, input_num_capsule, input_dim_capsule },
C.DataType.Float,
CC.GlorotUniformInitializer(),
computeDevice,
name: "W");
inputs = CC.Reshape(inputs, new int[] { 1, 1, input_num_capsule, input_dim_capsule }); // [1, 1, 1152, 8])
var inputs_hat = CC.ElementTimes(W, inputs);
inputs_hat = CC.ReduceSum(inputs_hat, new C.Axis(3));
inputs_hat = CC.Squeeze(inputs_hat);
C.Function outputs = null;
var zeros = new C.Constant(new int[] { num_capsule, 1, input_num_capsule }, C.DataType.Float, 0, computeDevice);
var b = CC.Combine(new C.VariableVector()
{
zeros
});
for (int i = 0; i < routings; i++)
{
var c = CC.Softmax(b, new C.Axis(0));
var batch_dot_result = CC.ElementTimes(c, inputs_hat);
batch_dot_result = CC.ReduceSum(batch_dot_result, new C.Axis(2));
batch_dot_result = CC.Squeeze(batch_dot_result);
outputs = squash(batch_dot_result, name: $"squashed_{i}", axis: 1);
if (i < (routings - 1))
{
outputs = CC.Reshape(outputs, new int[] { num_capsule, dim_capsule, 1 });
batch_dot_result = CC.ElementTimes(outputs, inputs_hat);
batch_dot_result = CC.ReduceSum(batch_dot_result, new C.Axis(1));
b = CC.Plus(b, batch_dot_result);
}
}
outputs = CC.Combine(new C.VariableVector()
{
outputs
}, name);
return(outputs);
}
C.Function get_mask_and_infer_from_last_dimension(C.Function inputs, C.Function mask)
{
if (mask == null)
{
var inputs_shape = inputs.Output.Shape.Dimensions.ToArray();
var ndims = inputs_shape.Length - 1;
var x = CC.Sqrt(CC.ReduceSum(CC.Square(inputs), new C.Axis(ndims - 1)));
x = CC.Squeeze(x);
System.Diagnostics.Debug.Assert(x.Output.Shape.Dimensions.Count == 1);
x = CC.Argmax(x, new C.Axis(0));
mask = CC.OneHotOp(x, numClass: (uint)inputs_shape[0], outputSparse: false, axis: new C.Axis(0));
}
mask = CC.Reshape(mask, mask.Output.Shape.AppendShape(new int[] { 1 }));
var masked = CC.ElementTimes(inputs, mask);
masked = CC.Flatten(masked);
masked = CC.Squeeze(masked);
return(masked);
}
