Como executar o gráfico define Tensorflow onde todas as variáveis estão no float16 em vez de no float32
Por padrão, as variáveis Tensorflow estão em float32. Para economizar memória, estou tentando executar no float16. No meu gráfico, em todos os lugares onde eu poderia definir o tipo de dados como float16, eu fiz. No entanto, recebo um erro quando executo o código
Aqui está o meu código abaixo.
import math
import numpy as np
import tensorflow as tf
vocabulary_size = 10
batch_size = 64
embedding_size = 100
num_inputs =4
num_sampled = 128
graph = tf.Graph()
with graph.as_default(): #took out " , tf.device('/cpu:0')"
train_dataset = tf.placeholder(tf.int32, shape=[batch_size, num_inputs ])
train_labels = tf.placeholder(tf.int32, shape=[batch_size, 1])
embeddings = tf.get_variable( 'embeddings', dtype=tf.float16,
initializer= tf.random_uniform([vocabulary_size, embedding_size], -1.0, 1.0, dtype=tf.float16) )
softmax_weights = tf.get_variable( 'softmax_weights', dtype=tf.float16,
initializer= tf.truncated_normal([vocabulary_size, embedding_size],
stddev=1.0 / math.sqrt(embedding_size), dtype=tf.float16 ) )
softmax_biases = tf.get_variable('softmax_biases', dtype=tf.float16,
initializer= tf.zeros([vocabulary_size], dtype=tf.float16), trainable=False )
embed = tf.nn.embedding_lookup(embeddings, train_dataset) #train data set is
embed_reshaped = tf.reshape( embed, [batch_size*num_inputs, embedding_size] )
segments= np.arange(batch_size).repeat(num_inputs)
averaged_embeds = tf.segment_mean(embed_reshaped, segments, name=None)
sam_sof_los = tf.nn.sampled_softmax_loss(weights=softmax_weights, biases=softmax_biases, inputs=averaged_embeds,
labels=train_labels, num_sampled=num_sampled, num_classes=vocabulary_size)
loss = tf.reduce_mean( sam_sof_los )
optimizer = tf.train.AdagradOptimizer(1.0).minimize(loss)
saver = tf.train.Saver()
E esta é a mensagem de erro
---------------------------------------------------------------------------
ValueError Traceback (most recent call last)
/usr/local/lib/python3.6/dist-packages/tensorflow/python/framework/op_def_library.py in _apply_op_helper(self, op_type_name, name, **keywords)
509 as_ref=input_arg.is_ref,
--> 510 preferred_dtype=default_dtype)
511 except TypeError as err:
/usr/local/lib/python3.6/dist-packages/tensorflow/python/framework/ops.py in internal_convert_to_tensor(value, dtype, name, as_ref, preferred_dtype, ctx)
1143 if ret is None:
-> 1144 ret = conversion_func(value, dtype=dtype, name=name, as_ref=as_ref)
1145
/usr/local/lib/python3.6/dist-packages/tensorflow/python/framework/ops.py in _TensorTensorConversionFunction(t, dtype, name, as_ref)
980 "Tensor conversion requested dtype %s for Tensor with dtype %s: %r" %
--> 981 (dtype.name, t.dtype.name, str(t)))
982 return t
ValueError: Tensor conversion requested dtype float16 for Tensor with dtype float32: 'Tensor("sampled_softmax_loss/Log:0", shape=(64, 1), dtype=float32)'
During handling of the above exception, another exception occurred:
TypeError Traceback (most recent call last)
<ipython-input-2-12d508b9e5d7> in <module>()
46
47 sam_sof_los = tf.nn.sampled_softmax_loss(weights=softmax_weights, biases=softmax_biases, inputs=averaged_embeds,
---> 48 labels=train_labels, num_sampled=num_sampled, num_classes=vocabulary_size)
49
50 loss = tf.reduce_mean( sam_sof_los )
/usr/local/lib/python3.6/dist-packages/tensorflow/python/ops/nn_impl.py in sampled_softmax_loss(weights, biases, labels, inputs, num_sampled, num_classes, num_true, sampled_values, remove_accidental_hits, partition_strategy, name, seed)
1347 partition_strategy=partition_strategy,
1348 name=name,
-> 1349 seed=seed)
1350 labels = array_ops.stop_gradient(labels, name="labels_stop_gradient")
1351 sampled_losses = nn_ops.softmax_cross_entropy_with_logits_v2(
/usr/local/lib/python3.6/dist-packages/tensorflow/python/ops/nn_impl.py in _compute_sampled_logits(weights, biases, labels, inputs, num_sampled, num_classes, num_true, sampled_values, subtract_log_q, remove_accidental_hits, partition_strategy, name, seed)
1126 if subtract_log_q:
1127 # Subtract log of Q(l), prior probability that l appears in sampled.
-> 1128 true_logits -= math_ops.log(true_expected_count)
1129 sampled_logits -= math_ops.log(sampled_expected_count)
1130
/usr/local/lib/python3.6/dist-packages/tensorflow/python/ops/math_ops.py in binary_op_wrapper(x, y)
860 with ops.name_scope(None, op_name, [x, y]) as name:
861 if isinstance(x, ops.Tensor) and isinstance(y, ops.Tensor):
--> 862 return func(x, y, name=name)
863 elif not isinstance(y, sparse_tensor.SparseTensor):
864 try:
/usr/local/lib/python3.6/dist-packages/tensorflow/python/ops/gen_math_ops.py in sub(x, y, name)
8316 if _ctx is None or not _ctx._eager_context.is_eager:
8317 _, _, _op = _op_def_lib._apply_op_helper(
-> 8318 "Sub", x=x, y=y, name=name)
8319 _result = _op.outputs[:]
8320 _inputs_flat = _op.inputs
/usr/local/lib/python3.6/dist-packages/tensorflow/python/framework/op_def_library.py in _apply_op_helper(self, op_type_name, name, **keywords)
544 "%s type %s of argument '%s'." %
545 (prefix, dtypes.as_dtype(attrs[input_arg.type_attr]).name,
--> 546 inferred_from[input_arg.type_attr]))
547
548 types = [values.dtype]
TypeError: Input 'y' of 'Sub' Op has type float32 that does not match type float16 of argument 'x'.
O erro vem da linhatf.nn.sampled_softmax_loss
.
No começo, pensei que talvez tf.segment_mean pudesse converter a saída como float32, então tentei converter o valor médio de _embeds para float16, mas ainda assim recebo o mesmo err
Na documentação, não parece haver uma maneira de definir nenhum tipo de dados em sampled_softmax_loss
https: //www.tensorflow.org/api_docs/python/tf/nn/sampled_softmax_los