split unary & binary operators into their own file

This commit is contained in:
Hieu Hoang 2016-09-19 15:57:41 +01:00
parent 8b55721206
commit 2a9d3de35a
3 changed files with 446 additions and 427 deletions

View File

@ -22,6 +22,8 @@
// SOFTWARE.
#include "node.h"
#include "node_operators_unary.h"
#include "node_operators_binary.h"
#include "tensor_operators.h"
namespace marian {
@ -107,435 +109,8 @@ struct ParamNode : public Node {
bool initialized_;
};
struct UnaryNodeOp : public Node {
ChainPtr a_;
template <typename ...Args>
UnaryNodeOp(ChainPtr a, Args ...args)
: Node(keywords::shape=a->shape(), //@TODO: Check keywords?
args...), a_(a) {}
void backward_numeric() {
backward();
}
};
struct LogitNodeOp : public UnaryNodeOp {
template <typename ...Args>
LogitNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = Sigma(_2),
val_, a_->val());
}
void backward() {
Element(_1 += _2 * _3 * (1 - _3),
a_->grad(), adj_, val_);
}
void check() {
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"logit\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct TanhNodeOp : public UnaryNodeOp {
template <typename ...Args>
TanhNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = Tanh(_2),
val_, a_->val());
}
void backward() {
Element(_1 += _2 * (1 - _3 * _3),
a_->grad(), adj_, val_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"tanh\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct SoftmaxNodeOp : public UnaryNodeOp {
template <typename ...Args>
SoftmaxNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
// B = softmax(A).
thrust::copy(a_->val().begin(), a_->val().end(), val_.begin());
// Safe version of softmax.
Softmax(&val_);
}
void backward() {
// For each row, the Jacobian times vector is given by:
// J * dy = p .* (dy - avg*1)
// where avg = p'*dy and p is the softmax output (probabilities).
//
// For more information, see sec. 2.5 of the following reference:
// André F. T. Martins and Ramon Astudillo.
// "From Softmax to Sparsemax: A Sparse Model of Attention and Multi-Label
// Classification." ICML 2016.
// http://jmlr.org/proceedings/papers/v48/martins16.pdf
SoftmaxGrad(a_->grad(), adj_, val_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"softmax\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct ArgmaxNodeOp : public UnaryNodeOp {
template <typename ...Args>
ArgmaxNodeOp(ChainPtr a, Args ...args)
: UnaryNodeOp(a, keywords::shape=newShape(a), args...) { }
void forward() {
// B = softmax(A).
Argmax(&val_, &a_->val());
}
void backward() {
}
Shape newShape(ChainPtr a) {
Shape shape = a->shape();
shape[1] = 1;
return shape;
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"argmax\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct LogNodeOp : public UnaryNodeOp {
template <typename ...Args>
LogNodeOp(Args ...args)
: UnaryNodeOp(args...) {}
void forward() {
Element(_1 = Log(_2), val_, a_->val());
}
void backward() {
Element(_1 += _2 * 1.f / _3,
a_->grad(), adj_, a_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"log\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct ExpNodeOp : public UnaryNodeOp {
template <typename ...Args>
ExpNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = Exp(_2), val_, a_->val());
}
void backward() {
Element(_1 += _2 * Exp(_3),
a_->grad(), adj_, a_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"exp\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct NegNodeOp : public UnaryNodeOp {
template <typename ...Args>
NegNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = -_2, val_, a_->val());
}
void backward() {
Element(_1 += -_2, a_->grad(), adj_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"-\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
/******************************************************/
struct BinaryNodeOp : public Node {
ChainPtr a_;
ChainPtr b_;
template <typename ...Args>
BinaryNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: Node(args...), a_(a), b_(b) {}
void backward_numeric() {
backward();
}
};
/*** Matrix Product ***/
struct DotNodeOp : public BinaryNodeOp {
template <typename ...Args>
DotNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b,
keywords::shape=newShape(a, b),
args...) { }
Shape newShape(ChainPtr a, ChainPtr b) {
Shape shape1 = a->shape();
Shape shape2 = b->shape();
UTIL_THROW_IF2(shape1[1] != shape2[0],
"matrix product requires dimensions to match");
shape1[1] = shape2[1];
return shape1;
}
void forward() {
// C = A*B
Prod(val_, a_->val(), b_->val(), false, false);
}
void backward() {
// D is the adjoint, the matrix of derivatives
// df/dA += D*B.T
// df/dB += A.T*D
// beta set to 1.0 in gemm, C = alpha * dot(A,B) + beta * C
// to sum gradients from different graph parts
Prod(a_->grad(), adj_, b_->val(), false, true, 1.0);
Prod(b_->grad(), a_->val(), adj_, true, false, 1.0);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"×\", style=\"filled\", fillcolor=\"orange\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct PlusNodeOp : public BinaryNodeOp {
template <typename ...Args>
PlusNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 + _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2,
a_->grad(), adj_);
Element(_1 += _2,
b_->grad(), adj_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"+\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct MinusNodeOp : public BinaryNodeOp {
template <typename ...Args>
MinusNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 - _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2,
a_->grad(), adj_);
Element(_1 -= _2,
b_->grad(), adj_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"-\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct MultNodeOp : public BinaryNodeOp {
template <typename ...Args>
MultNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 * _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2 * _3,
a_->grad(), adj_, b_->val());
Element(_1 += _2 * _3,
b_->grad(), adj_, a_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct DivNodeOp : public BinaryNodeOp {
template <typename ...Args>
DivNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 / _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2 * 1.0f / _3,
a_->grad(), adj_, b_->val());
Element(_1 -= _2 * _3 / (_4 * _4),
b_->grad(), adj_, a_->val(), b_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"÷\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
// Cross-entropy node. It computes -b*log(softmax(a)), summing rowwise.
struct CrossEntropyNodeOp : public BinaryNodeOp {
template <typename ...Args>
CrossEntropyNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b,
keywords::shape=newShape(a, b),
args...) { }
Shape newShape(ChainPtr a, ChainPtr b) {
Shape shape1 = a->shape();
Shape shape2 = b->shape();
UTIL_THROW_IF2(shape1[0] != shape2[0] || shape1[1] != shape2[1],
"cross entropy requires dimensions to match");
shape1[1] = 1;
return shape1;
}
// We're caching the softmax probabilities here because we'll need them for
// the backward computation.
void forward() {
// C = -dot(B, log(softmax(A))).
if (probs_) {
probs_.set(0.0);
} else {
probs_.allocate(a_->val().shape(), 0.0);
}
thrust::copy(a_->val().begin(), a_->val().end(), probs_.begin());
Softmax(&probs_); // Safe version of softmax.
Tensor result(a_->val().shape());
Element(_1 = -_2 * Log(_3), result, b_->val(), probs_);
SumRowwise(result, val_);
}
// @TODO: In most cases it's wasteful to compute the derivative with respect
// to the second input which is typically an input node in the computation
// graph. In general the backward functions can skip the computation of
// gradients wrt input nodes.
void backward() {
// For each row, the first input derivative is given by adj * (p - y),
// where y is the gold label distribution (e.g. one hot vector) and
// p is the softmax output (probabilities).
// The second input derivative is -adj*log(p).
Tensor result(probs_.shape());
// Compute first input derivative.
Element(_1 = _2 - _3, result, probs_, b_->val());
ScaleRowwise(result, adj_);
Element(_1 += _2, a_->grad(), result);
// Compute second input derivative.
Element(_1 = -Log(_2), result, probs_); // @TODO: use a cached log here.
ScaleRowwise(result, adj_);
Element(_1 += _2, b_->grad(), result);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"cross_entropy\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
protected:
Tensor probs_;
};
}

241
src/node_operators_binary.h Normal file
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@ -0,0 +1,241 @@
#include "node.h"
#include "tensor_operators.h"
namespace marian {
struct BinaryNodeOp : public Node {
ChainPtr a_;
ChainPtr b_;
template <typename ...Args>
BinaryNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: Node(args...), a_(a), b_(b) {}
void backward_numeric() {
backward();
}
};
/*** Matrix Product ***/
struct DotNodeOp : public BinaryNodeOp {
template <typename ...Args>
DotNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b,
keywords::shape=newShape(a, b),
args...) { }
Shape newShape(ChainPtr a, ChainPtr b) {
Shape shape1 = a->shape();
Shape shape2 = b->shape();
UTIL_THROW_IF2(shape1[1] != shape2[0],
"matrix product requires dimensions to match");
shape1[1] = shape2[1];
return shape1;
}
void forward() {
// C = A*B
Prod(val_, a_->val(), b_->val(), false, false);
}
void backward() {
// D is the adjoint, the matrix of derivatives
// df/dA += D*B.T
// df/dB += A.T*D
// beta set to 1.0 in gemm, C = alpha * dot(A,B) + beta * C
// to sum gradients from different graph parts
Prod(a_->grad(), adj_, b_->val(), false, true, 1.0);
Prod(b_->grad(), a_->val(), adj_, true, false, 1.0);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"×\", style=\"filled\", fillcolor=\"orange\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct PlusNodeOp : public BinaryNodeOp {
template <typename ...Args>
PlusNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 + _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2,
a_->grad(), adj_);
Element(_1 += _2,
b_->grad(), adj_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"+\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct MinusNodeOp : public BinaryNodeOp {
template <typename ...Args>
MinusNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 - _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2,
a_->grad(), adj_);
Element(_1 -= _2,
b_->grad(), adj_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"-\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct MultNodeOp : public BinaryNodeOp {
template <typename ...Args>
MultNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 * _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2 * _3,
a_->grad(), adj_, b_->val());
Element(_1 += _2 * _3,
b_->grad(), adj_, a_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct DivNodeOp : public BinaryNodeOp {
template <typename ...Args>
DivNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b, keywords::shape=a->shape(), args...) { }
void forward() {
Element(_1 = _2 / _3,
val_, a_->val(), b_->val());
}
void backward() {
Element(_1 += _2 * 1.0f / _3,
a_->grad(), adj_, b_->val());
Element(_1 -= _2 * _3 / (_4 * _4),
b_->grad(), adj_, a_->val(), b_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"÷\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
// Cross-entropy node. It computes -b*log(softmax(a)), summing rowwise.
struct CrossEntropyNodeOp : public BinaryNodeOp {
template <typename ...Args>
CrossEntropyNodeOp(ChainPtr a, ChainPtr b, Args ...args)
: BinaryNodeOp(a, b,
keywords::shape=newShape(a, b),
args...) { }
Shape newShape(ChainPtr a, ChainPtr b) {
Shape shape1 = a->shape();
Shape shape2 = b->shape();
UTIL_THROW_IF2(shape1[0] != shape2[0] || shape1[1] != shape2[1],
"cross entropy requires dimensions to match");
shape1[1] = 1;
return shape1;
}
// We're caching the softmax probabilities here because we'll need them for
// the backward computation.
void forward() {
// C = -dot(B, log(softmax(A))).
if (probs_) {
probs_.set(0.0);
} else {
probs_.allocate(a_->val().shape(), 0.0);
}
thrust::copy(a_->val().begin(), a_->val().end(), probs_.begin());
Softmax(&probs_); // Safe version of softmax.
Tensor result(a_->val().shape());
Element(_1 = -_2 * Log(_3), result, b_->val(), probs_);
SumRowwise(result, val_);
}
// @TODO: In most cases it's wasteful to compute the derivative with respect
// to the second input which is typically an input node in the computation
// graph. In general the backward functions can skip the computation of
// gradients wrt input nodes.
void backward() {
// For each row, the first input derivative is given by adj * (p - y),
// where y is the gold label distribution (e.g. one hot vector) and
// p is the softmax output (probabilities).
// The second input derivative is -adj*log(p).
Tensor result(probs_.shape());
// Compute first input derivative.
Element(_1 = _2 - _3, result, probs_, b_->val());
ScaleRowwise(result, adj_);
Element(_1 += _2, a_->grad(), result);
// Compute second input derivative.
Element(_1 = -Log(_2), result, probs_); // @TODO: use a cached log here.
ScaleRowwise(result, adj_);
Element(_1 += _2, b_->grad(), result);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"cross_entropy\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl;
ss << "\"" << b_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
protected:
Tensor probs_;
};
}

203
src/node_operators_unary.h Normal file
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@ -0,0 +1,203 @@
#include "node.h"
#include "tensor_operators.h"
namespace marian {
struct UnaryNodeOp : public Node {
ChainPtr a_;
template <typename ...Args>
UnaryNodeOp(ChainPtr a, Args ...args)
: Node(keywords::shape=a->shape(), //@TODO: Check keywords?
args...), a_(a) {}
void backward_numeric() {
backward();
}
};
struct LogitNodeOp : public UnaryNodeOp {
template <typename ...Args>
LogitNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = Sigma(_2),
val_, a_->val());
}
void backward() {
Element(_1 += _2 * _3 * (1 - _3),
a_->grad(), adj_, val_);
}
void check() {
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"logit\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct TanhNodeOp : public UnaryNodeOp {
template <typename ...Args>
TanhNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = Tanh(_2),
val_, a_->val());
}
void backward() {
Element(_1 += _2 * (1 - _3 * _3),
a_->grad(), adj_, val_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"tanh\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct SoftmaxNodeOp : public UnaryNodeOp {
template <typename ...Args>
SoftmaxNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
// B = softmax(A).
thrust::copy(a_->val().begin(), a_->val().end(), val_.begin());
// Safe version of softmax.
Softmax(&val_);
}
void backward() {
// For each row, the Jacobian times vector is given by:
// J * dy = p .* (dy - avg*1)
// where avg = p'*dy and p is the softmax output (probabilities).
//
// For more information, see sec. 2.5 of the following reference:
// André F. T. Martins and Ramon Astudillo.
// "From Softmax to Sparsemax: A Sparse Model of Attention and Multi-Label
// Classification." ICML 2016.
// http://jmlr.org/proceedings/papers/v48/martins16.pdf
SoftmaxGrad(a_->grad(), adj_, val_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"softmax\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct ArgmaxNodeOp : public UnaryNodeOp {
template <typename ...Args>
ArgmaxNodeOp(ChainPtr a, Args ...args)
: UnaryNodeOp(a, keywords::shape=newShape(a), args...) { }
void forward() {
// B = softmax(A).
Argmax(&val_, &a_->val());
}
void backward() {
}
Shape newShape(ChainPtr a) {
Shape shape = a->shape();
shape[1] = 1;
return shape;
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"argmax\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct LogNodeOp : public UnaryNodeOp {
template <typename ...Args>
LogNodeOp(Args ...args)
: UnaryNodeOp(args...) {}
void forward() {
Element(_1 = Log(_2), val_, a_->val());
}
void backward() {
Element(_1 += _2 * 1.f / _3,
a_->grad(), adj_, a_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"log\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct ExpNodeOp : public UnaryNodeOp {
template <typename ...Args>
ExpNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = Exp(_2), val_, a_->val());
}
void backward() {
Element(_1 += _2 * Exp(_3),
a_->grad(), adj_, a_->val());
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"exp\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
struct NegNodeOp : public UnaryNodeOp {
template <typename ...Args>
NegNodeOp(Args ...args)
: UnaryNodeOp(args...) { }
void forward() {
Element(_1 = -_2, val_, a_->val());
}
void backward() {
Element(_1 += -_2, a_->grad(), adj_);
}
virtual std::string graphviz() {
std::stringstream ss;
ss << "\"" << this << "\" [shape=\"box\", label=\"-\", style=\"filled\", fillcolor=\"yellow\"]" << std::endl;
ss << "\"" << a_ << "\" -> \"" << this << "\"" << std::endl << std::endl;
return ss.str();
};
};
}