From 8a59718fd641cb1aa885842ad5e62f9fac1dad94 Mon Sep 17 00:00:00 2001 From: Matthew Honnibal Date: Sun, 20 Aug 2017 18:17:35 +0200 Subject: [PATCH] Fix fine-tuning --- spacy/_ml.py | 23 ++++++++++++----------- 1 file changed, 12 insertions(+), 11 deletions(-) diff --git a/spacy/_ml.py b/spacy/_ml.py index b3b0d3e46..b385e2e53 100644 --- a/spacy/_ml.py +++ b/spacy/_ml.py @@ -359,8 +359,6 @@ def get_token_vectors(tokens_attrs_vectors, drop=0.): def backward(d_output, sgd=None): return (tokens, d_output) return vectors, backward - - def fine_tune(embedding, combine=None): if combine is not None: raise NotImplementedError( @@ -372,22 +370,25 @@ def fine_tune(embedding, combine=None): vecs, bp_vecs = embedding.begin_update(docs, drop=drop) flat_tokvecs = embedding.ops.flatten(tokvecs) flat_vecs = embedding.ops.flatten(vecs) + alpha = model.mix + minus = 1-model.mix output = embedding.ops.unflatten( - (model.mix[0] * flat_vecs + model.mix[1] * flat_tokvecs), - lengths) + (alpha * flat_tokvecs + minus * flat_vecs), lengths) def fine_tune_bwd(d_output, sgd=None): - bp_vecs(d_output, sgd=sgd) flat_grad = model.ops.flatten(d_output) - model.d_mix[1] += flat_tokvecs.dot(flat_grad.T).sum() - model.d_mix[0] += flat_vecs.dot(flat_grad.T).sum() - if sgd is not None: - sgd(model._mem.weights, model._mem.gradient, key=model.id) + model.d_mix += flat_tokvecs.dot(flat_grad.T).sum() + model.d_mix += 1-flat_vecs.dot(flat_grad.T).sum() + + bp_vecs([d_o * minus for d_o in d_output], sgd=sgd) + d_output = [d_o * alpha for d_o in d_output] + sgd(model._mem.weights, model._mem.gradient, key=model.id) + model.mix = model.ops.xp.minimum(model.mix, 1.0) return d_output return output, fine_tune_bwd model = wrap(fine_tune_fwd, embedding) - model.mix = model._mem.add((model.id, 'mix'), (2,)) - model.mix.fill(1.) + model.mix = model._mem.add((model.id, 'mix'), (1,)) + model.mix.fill(0.0) model.d_mix = model._mem.add_gradient((model.id, 'd_mix'), (model.id, 'mix')) return model