SwitchingForwardingDescriptor Class Reference

Chooses from different inputs based on the the time index modulo (the number of ForwardingDescriptors given as inputs). More...

#include <nnet-descriptor.h>

Inheritance diagram for SwitchingForwardingDescriptor:

Collaboration diagram for SwitchingForwardingDescriptor:

Public Member Functions
virtual Cindex	MapToInput (const Index &ind) const
virtual int32	Dim (const Nnet &nnet) const
virtual ForwardingDescriptor *	Copy () const
virtual void	WriteConfig (std::ostream &os, const std::vector< std::string > &node_names) const
virtual int32	Modulus () const
	This function is for use in things like clockwork RNNs, where shifting the time of the inputs and outputs of the network by some multiple integer n would leave things the same, but shifting by non-multiples would change the network structure. More...
virtual void	GetNodeDependencies (std::vector< int32 > *node_indexes) const
	This function appends to "node_indexes" all the node indexes. More...
virtual BaseFloat	GetScaleForNode (int32 node_index) const
	This function returns the scale on the node-index 'node_index' when it appears in expressions inside this descriptor, or +infinity if it does not appear. More...
	SwitchingForwardingDescriptor (std::vector< ForwardingDescriptor *> &src)
virtual	~SwitchingForwardingDescriptor ()
Public Member Functions inherited from ForwardingDescriptor
virtual	~ForwardingDescriptor ()
	ForwardingDescriptor ()

Private Attributes
std::vector< ForwardingDescriptor * >	src_

Detailed Description

Chooses from different inputs based on the the time index modulo (the number of ForwardingDescriptors given as inputs).

This is rarely if ever used. Written form is: `Switch(<descriptor>, <descriptor> [, <descriptor> ...])` e.g. `Switch(tdnn2a, tdnn2b, tdnn2c)`

Definition at line 210 of file nnet-descriptor.h.

Constructor & Destructor Documentation

SwitchingForwardingDescriptor()

SwitchingForwardingDescriptor ( std::vector< ForwardingDescriptor *> &  src )

inline

Definition at line 227 of file nnet-descriptor.h.

                                                                      :
      src_(src) { }

~SwitchingForwardingDescriptor()

virtual ~SwitchingForwardingDescriptor ( )

inlinevirtual

Definition at line 229 of file nnet-descriptor.h.

References kaldi::DeletePointers().

{ DeletePointers(&src_); }

Member Function Documentation

Copy()

ForwardingDescriptor * Copy ( ) const

virtual

Implements ForwardingDescriptor.

Definition at line 161 of file nnet-descriptor.cc.

References kaldi::cu::Copy(), and rnnlm::i.

                                                                {
  std::vector<ForwardingDescriptor*> src_copy(src_.size());
  for (size_t i = 0; i < src_.size(); i++)
    src_copy[i] = src_[i]->Copy();
  return new SwitchingForwardingDescriptor(src_copy);
}

Dim()

virtual int32 Dim ( const Nnet &  nnet ) const

inlinevirtual

Implements ForwardingDescriptor.

Definition at line 213 of file nnet-descriptor.h.

References ForwardingDescriptor::Copy(), ForwardingDescriptor::GetNodeDependencies(), ForwardingDescriptor::GetScaleForNode(), ForwardingDescriptor::Modulus(), and ForwardingDescriptor::WriteConfig().

{ return src_[0]->Dim(nnet); }

GetNodeDependencies()

void GetNodeDependencies ( std::vector< int32 > *  node_indexes ) const

virtual

This function appends to "node_indexes" all the node indexes.

Implements ForwardingDescriptor.

Definition at line 146 of file nnet-descriptor.cc.

References Descriptor::GetNodeDependencies(), and rnnlm::i.

                                          {
  for (size_t i = 0; i < src_.size(); i++)
    src_[i]->GetNodeDependencies(node_indexes);
}

GetScaleForNode()

BaseFloat GetScaleForNode ( int32  node_index ) const

virtual

This function returns the scale on the node-index 'node_index' when it appears in expressions inside this descriptor, or +infinity if it does not appear.

E.g. if the descriptor is just `Scale(tdnn2, 2.0)` and the node index for `tdnn2` is 4, then GetScaleForNode(4) would return 2.0. If a particular node_index > 0 appears in different sub-expressions of the descriptor with different scales it is an error (it's not supported) and this function would crash.

Implements ForwardingDescriptor.

Definition at line 473 of file nnet-descriptor.cc.

References rnnlm::i, and KALDI_ERR.

                            {
  BaseFloat inf = std::numeric_limits<BaseFloat>::infinity(),
      ans = inf;
  for (size_t i = 0; i < src_.size(); i++) {
    BaseFloat this_ans = src_[i]->GetScaleForNode(node_index);
    if (this_ans != inf) {
      if (ans != inf && ans != this_ans)
        KALDI_ERR << "Invalid Descriptor encountered: for node-index "
                  << node_index << ", got two different scales "
                  << this_ans << " vs. " << ans;
      ans = this_ans;
    }
  }
  return ans;
}

MapToInput()

Cindex MapToInput ( const Index &  ind ) const

virtual

Implements ForwardingDescriptor.

Definition at line 152 of file nnet-descriptor.cc.

References KALDI_ASSERT, and Index::t.

                                                                       {
  KALDI_ASSERT(!src_.empty());
  int32 size = src_.size(), mod = ind.t % size;
  // next line gets "mathematical" modulus, not broken "C" modulus.
  if (mod < 0) mod += size;
  return src_[mod]->MapToInput(ind);
}

Modulus()

int32 Modulus ( ) const

virtual

This function is for use in things like clockwork RNNs, where shifting the time of the inputs and outputs of the network by some multiple integer n would leave things the same, but shifting by non-multiples would change the network structure.

It returns the smallest modulus to which this descriptor is invariant; the lowest common multiple of all descriptors in the network gives you the modulus for the whole network.

Reimplemented from ForwardingDescriptor.

Definition at line 466 of file nnet-descriptor.cc.

References rnnlm::i, kaldi::Lcm(), and ConstantSumDescriptor::Modulus().

                                                   {
  int32 ans = src_.size();;
  for (size_t i = 0; i < src_.size(); i++)
    ans = Lcm(ans, src_[i]->Modulus());
  return ans;
}

WriteConfig()

void WriteConfig ( std::ostream &  os, const std::vector< std::string > &  node_names  ) const

virtual

Implements ForwardingDescriptor.

Definition at line 169 of file nnet-descriptor.cc.

References rnnlm::i, and KALDI_ASSERT.

                                                  {
  KALDI_ASSERT(!src_.empty());
  os << "Switch(";
  for (size_t i = 0; i < src_.size(); i++) {
    src_[i]->WriteConfig(os, node_names);
    if (i + 1 < src_.size())
      os << ", ";
  }
  os << ")";
}

Member Data Documentation

src_

std::vector<ForwardingDescriptor*> src_

private

Definition at line 232 of file nnet-descriptor.h.

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The documentation for this class was generated from the following files:

• nnet3/nnet-descriptor.h
• nnet3/nnet-descriptor.cc