def slice_arrays(arrays, indices, contiguous=True): """Slices batches out of provided arrays (workaround for eager tensors). Unfortunately eager tensors don't have the same slicing behavior as Numpy arrays (they folow the same slicing behavior as symbolic TF tensors), hence we cannot use `generic_utils.slice_arrays` directly and we have to implement this workaround based on `concat`. This has a performance cost. Arguments: arrays: Single array or list of arrays. indices: List of indices in the array that should be included in the output batch. contiguous: Boolean flag indicating whether the indices are contiguous. Returns: Slice of data (either single array or list of arrays). """ if any(tensor_util.is_tensor(x) for x in arrays): converted_to_list = False if not isinstance(arrays, list): converted_to_list = True arrays = [arrays] if not contiguous: entries = [[x[i:i + 1] for i in indices] for x in arrays] slices = [array_ops.concat(x, axis=0) for x in entries] else: slices = [x[indices[0]:indices[-1] + 1] for x in arrays] if converted_to_list: slices = slices[0] return slices else: return generic_utils.slice_arrays(arrays, indices)
def slice_arrays(arrays, indices, contiguous=True): """Slices batches out of provided arrays (workaround for eager tensors). Unfortunately eager tensors don't have the same slicing behavior as Numpy arrays (they follow the same slicing behavior as symbolic TF tensors), hence we cannot use `generic_utils.slice_arrays` directly and we have to implement this workaround based on `concat`. This has a performance cost. Arguments: arrays: Single array or list of arrays. indices: List of indices in the array that should be included in the output batch. contiguous: Boolean flag indicating whether the indices are contiguous. Returns: Slice of data (either single array or list of arrays). """ if any(tensor_util.is_tensor(x) for x in arrays): converted_to_list = False if not isinstance(arrays, list): converted_to_list = True arrays = [arrays] if not contiguous: entries = [[x[i:i + 1] for i in indices] for x in arrays] slices = [array_ops.concat(x, axis=0) for x in entries] else: slices = [x[indices[0]:indices[-1] + 1] for x in arrays] if converted_to_list: slices = slices[0] return slices else: return generic_utils.slice_arrays(arrays, indices)
def predict_loop(model, inputs, batch_size=32, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Keras Model instance. inputs: list of tensors to be fed to `f`. batch_size: integer batch size. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring `_predict_loop` finished. Ignored with the default value of `None`. Returns: Array of predictions (if the model has a single output) or list of arrays of predictions (if the model has multiple outputs). """ model._make_predict_function() f = model.predict_function if model.uses_learning_phase and not isinstance(K.learning_phase(), int): ins = inputs + [0] else: ins = inputs num_samples = training_utils.check_num_samples(inputs, batch_size, steps, 'steps') if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) indices_for_conversion_to_dense = [] for i in range(len(model._feed_inputs)): if (issparse is not None and issparse(inputs[i]) and not K.is_sparse(model._feed_inputs[i])): indices_for_conversion_to_dense.append(i) if steps is not None: # Step-based predictions. # Since we do not know how many samples # we will see, we cannot pre-allocate # the returned Numpy arrays. # Instead, we store one array per batch seen # and concatenate them upon returning. unconcatenated_outs = [] for step in range(steps): batch_outs = f(ins) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if step == 0: for batch_out in batch_outs: unconcatenated_outs.append([]) for i, batch_out in enumerate(batch_outs): unconcatenated_outs[i].append(batch_out) if verbose == 1: progbar.update(step + 1) if len(unconcatenated_outs) == 1: return np.concatenate(unconcatenated_outs[0], axis=0) return [ np.concatenate(unconcatenated_outs[i], axis=0) for i in range(len(unconcatenated_outs)) ] else: # Sample-based predictions. outs = [] batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if ins and isinstance(ins[-1], int): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) for i in indices_for_conversion_to_dense: ins_batch[i] = ins_batch[i].toarray() batch_outs = f(ins_batch) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if batch_index == 0: # Pre-allocate the results arrays. for batch_out in batch_outs: shape = (num_samples, ) + batch_out.shape[1:] outs.append(np.zeros(shape, dtype=batch_out.dtype)) for i, batch_out in enumerate(batch_outs): outs[i][batch_start:batch_end] = batch_out if verbose == 1: progbar.update(batch_end) if len(outs) == 1: return outs[0] return outs
def test_slice_arrays(self): input_a = np.random.random((10, 3)) slice_arrays(None) slice_arrays(input_a, 0) slice_arrays(input_a, 0, 1) slice_arrays(input_a, stop=2) input_a = [None, [1, 1], None, [1, 1]] slice_arrays(input_a, 0) slice_arrays(input_a, 0, 1) slice_arrays(input_a, stop=2) input_a = [None] slice_arrays(input_a, 0) slice_arrays(input_a, 0, 1) slice_arrays(input_a, stop=2) input_a = None slice_arrays(input_a, 0) slice_arrays(input_a, 0, 1) slice_arrays(input_a, stop=2)
def fit_loop(model, inputs, targets, sample_weights=None, batch_size=None, epochs=100, verbose=1, callbacks=None, val_inputs=None, val_targets=None, val_sample_weights=None, shuffle=True, callback_metrics=None, initial_epoch=0, steps_per_epoch=None, validation_steps=None): """Abstract fit function for arrays of data. Arguments: model: Keras Model instance. inputs: List of input arrays. targets: List of target arrays. sample_weights: Optional list of sample weight arrays. batch_size: Integer batch size or None if unknown. epochs: Number of times to iterate over the data verbose: Verbosity mode, 0, 1 or 2 callbacks: List of callbacks to be called during training val_inputs: List of input arrays. val_targets: List of target arrays. val_sample_weights: Optional list of sample weight arrays. shuffle: Whether to shuffle the data at the beginning of each epoch callback_metrics: List of strings, the display names of the metrics passed to the callbacks. They should be the concatenation of list the display names of the outputs of `f` and the list of display names of the outputs of `f_val`. initial_epoch: Epoch at which to start training (useful for resuming a previous training run) steps_per_epoch: Total number of steps (batches of samples) before declaring one epoch finished and starting the next epoch. Ignored with the default value of `None`. validation_steps: Number of steps to run validation for (only if doing validation from data tensors). Ignored with the default value of `None`. Returns: `History` object. Raises: ValueError: in case of invalid arguments. """ model._make_train_function() f = model.train_function sample_weights = sample_weights or [] val_sample_weights = val_sample_weights or [] if model.uses_learning_phase and not isinstance(K.learning_phase(), int): ins = inputs + targets + sample_weights + [1] if val_inputs: val_ins = val_inputs + val_targets + val_sample_weights + [1] else: ins = inputs + targets + sample_weights if val_inputs: val_ins = val_inputs + val_targets + val_sample_weights if not val_inputs: val_ins = [] do_validation = False if val_inputs: do_validation = True if verbose and inputs and hasattr(inputs[0], 'shape') and hasattr( val_inputs[0], 'shape'): print('Train on %d samples, validate on %d samples' % (inputs[0].shape[0], val_inputs[0].shape[0])) if validation_steps: do_validation = True if steps_per_epoch is None: raise ValueError('Can only use `validation_steps` ' 'when doing step-wise ' 'training, i.e. `steps_per_epoch` ' 'must be set.') out_labels = model.metrics_names if do_validation: callback_metrics = copy.copy(out_labels) + [ 'val_' + n for n in out_labels ] else: callback_metrics = copy.copy(out_labels) num_train_samples = training_utils.check_num_samples( ins, batch_size, steps_per_epoch, 'steps_per_epoch') if num_train_samples is not None: index_array = np.arange(num_train_samples) model.history = cbks.History() all_callbacks = [cbks.BaseLogger( stateful_metrics=model.stateful_metric_names)] if verbose: if steps_per_epoch is not None: count_mode = 'steps' else: count_mode = 'samples' all_callbacks.append( cbks.ProgbarLogger( count_mode, stateful_metrics=model.stateful_metric_names)) all_callbacks += (callbacks or []) + [model.history] callbacks = cbks.CallbackList(all_callbacks) out_labels = out_labels or [] # it's possible to callback a different model than self # (used by Sequential models) if hasattr(model, 'callback_model') and model.callback_model: callback_model = model.callback_model else: callback_model = model callbacks.set_model(callback_model) callbacks.set_params({ 'batch_size': batch_size, 'epochs': epochs, 'steps': steps_per_epoch, 'samples': num_train_samples, 'verbose': verbose, 'do_validation': do_validation, 'metrics': callback_metrics or [], }) callbacks.on_train_begin() callback_model.stop_training = False for cbk in callbacks: cbk.validation_data = val_ins # To prevent a slowdown, we find beforehand the arrays that need conversion. feed = model._feed_inputs + model._feed_targets + model._feed_sample_weights indices_for_conversion_to_dense = [] for i in range(len(feed)): if issparse is not None and issparse(ins[i]) and not K.is_sparse(feed[i]): indices_for_conversion_to_dense.append(i) for epoch in range(initial_epoch, epochs): # Reset stateful metrics for m in model.metrics: if isinstance(m, Layer): m.reset_states() # Update callbacks callbacks.on_epoch_begin(epoch) epoch_logs = {} if steps_per_epoch is not None: for step_index in range(steps_per_epoch): batch_logs = {} batch_logs['batch'] = step_index batch_logs['size'] = 1 callbacks.on_batch_begin(step_index, batch_logs) outs = f(ins) if not isinstance(outs, list): outs = [outs] for l, o in zip(out_labels, outs): batch_logs[l] = o callbacks.on_batch_end(step_index, batch_logs) if callback_model.stop_training: break if do_validation: val_outs = test_loop( model, val_inputs, val_targets, sample_weights=val_sample_weights, batch_size=batch_size, steps=validation_steps, verbose=0) if not isinstance(val_outs, list): val_outs = [val_outs] # Same labels assumed. for l, o in zip(out_labels, val_outs): epoch_logs['val_' + l] = o else: if shuffle == 'batch': index_array = training_utils.batch_shuffle(index_array, batch_size) elif shuffle: np.random.shuffle(index_array) batches = make_batches(num_train_samples, batch_size) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] try: if isinstance(ins[-1], int): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) except TypeError: raise TypeError('TypeError while preparing batch. ' 'If using HDF5 input data, ' 'pass shuffle="batch".') batch_logs = {} batch_logs['batch'] = batch_index batch_logs['size'] = len(batch_ids) callbacks.on_batch_begin(batch_index, batch_logs) for i in indices_for_conversion_to_dense: ins_batch[i] = ins_batch[i].toarray() outs = f(ins_batch) if not isinstance(outs, list): outs = [outs] for l, o in zip(out_labels, outs): batch_logs[l] = o callbacks.on_batch_end(batch_index, batch_logs) if callback_model.stop_training: break if batch_index == len(batches) - 1: # Last batch. if do_validation: val_outs = test_loop( model, val_inputs, val_targets, sample_weights=val_sample_weights, batch_size=batch_size, verbose=0) if not isinstance(val_outs, list): val_outs = [val_outs] # Same labels assumed. for l, o in zip(out_labels, val_outs): epoch_logs['val_' + l] = o callbacks.on_epoch_end(epoch, epoch_logs) if callback_model.stop_training: break callbacks.on_train_end() return model.history
def predict_loop(model, inputs, batch_size=32, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Keras Model instance. inputs: list of tensors to be fed to `f`. batch_size: integer batch size. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring `_predict_loop` finished. Ignored with the default value of `None`. Returns: Array of predictions (if the model has a single output) or list of arrays of predictions (if the model has multiple outputs). """ model._make_predict_function() f = model.predict_function if model.uses_learning_phase and not isinstance(K.learning_phase(), int): ins = inputs + [0] else: ins = inputs num_samples = training_utils.check_num_samples( inputs, batch_size, steps, 'steps') if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) indices_for_conversion_to_dense = [] for i in range(len(model._feed_inputs)): if (issparse is not None and issparse(inputs[i]) and not K.is_sparse(model._feed_inputs[i])): indices_for_conversion_to_dense.append(i) if steps is not None: # Step-based predictions. # Since we do not know how many samples # we will see, we cannot pre-allocate # the returned Numpy arrays. # Instead, we store one array per batch seen # and concatenate them upon returning. unconcatenated_outs = [] for step in range(steps): batch_outs = f(ins) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if step == 0: for batch_out in batch_outs: unconcatenated_outs.append([]) for i, batch_out in enumerate(batch_outs): unconcatenated_outs[i].append(batch_out) if verbose == 1: progbar.update(step + 1) if len(unconcatenated_outs) == 1: return np.concatenate(unconcatenated_outs[0], axis=0) return [ np.concatenate(unconcatenated_outs[i], axis=0) for i in range(len(unconcatenated_outs)) ] else: # Sample-based predictions. outs = [] batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if ins and isinstance(ins[-1], int): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) for i in indices_for_conversion_to_dense: ins_batch[i] = ins_batch[i].toarray() batch_outs = f(ins_batch) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if batch_index == 0: # Pre-allocate the results arrays. for batch_out in batch_outs: shape = (num_samples,) + batch_out.shape[1:] outs.append(np.zeros(shape, dtype=batch_out.dtype)) for i, batch_out in enumerate(batch_outs): outs[i][batch_start:batch_end] = batch_out if verbose == 1: progbar.update(batch_end) if len(outs) == 1: return outs[0] return outs
def predict_loop(model, ins, batch_size=32, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: ins: list of tensors to be fed to `f`. batch_size: integer batch size. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring `_predict_loop` finished. Ignored with the default value of `None`. Returns: Array of predictions (if the model has a single output) or list of arrays of predictions (if the model has multiple outputs). """ K.set_learning_phase(False) num_samples = model._check_num_samples(ins, batch_size, steps, 'steps') if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) outs = [] batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if ins and isinstance(ins[-1], float): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) ins_batch_converted = [] for ib in ins_batch: ins_batch_converted.append( ops.convert_to_tensor(ib, dtype=K.floatx())) eager_model_inputs = [] for i in range(len(model.inputs)): eager_model_inputs.append(ins_batch_converted[i]) if len(eager_model_inputs) == 1: if model._expects_training_arg: batch_outs = model.call(eager_model_inputs[0], training=False) else: batch_outs = model.call(eager_model_inputs[0]) else: if model._expects_training_arg: batch_outs = model.call(eager_model_inputs, training=False) else: batch_outs = model.call(eager_model_inputs) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if batch_index == 0: # Pre-allocate the results arrays. for batch_out in batch_outs: dims = batch_out.shape[1:].dims dims_list = [d.value for d in dims] shape = (num_samples, ) + tuple(dims_list) outs.append( np.zeros(shape, dtype=batch_out.dtype.as_numpy_dtype)) for i, batch_out in enumerate(batch_outs): outs[i][batch_start:batch_end] = batch_out if verbose == 1: progbar.update(batch_end) if len(outs) == 1: return outs[0] return outs
def test_loop(model, inputs, targets, sample_weights=None, batch_size=None, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Model instance that is being evaluated in Eager mode. inputs: List of input arrays. targets: List of target arrays. sample_weights: Optional list of sample weight arrays. batch_size: integer batch size or `None`. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring predictions finished. Ignored with the default value of `None`. Returns: Scalar loss (if the model has a single output and no metrics) or list of scalars (if the model has multiple outputs and/or metrics). The attribute `model.metrics_names` will give you the display labels for the scalar outputs. """ with backend.learning_phase_scope(0): feed_data = inputs + targets if sample_weights: feed_data += sample_weights num_samples = training_utils.check_num_samples( feed_data, batch_size=batch_size, steps=steps, steps_name='steps') outs = [] if verbose == 1: progbar = Progbar(target=num_samples) batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] inputs_batch = slice_arrays(inputs, batch_ids) targets_batch = slice_arrays(targets, batch_ids) if sample_weights: sample_weights_batch = slice_arrays(sample_weights, batch_ids) else: sample_weights_batch = None inputs_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) for val in inputs_batch] targets_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) for val in targets_batch] if sample_weights: sample_weights_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) if val is not None else None for val in sample_weights_batch] loss_outs, loss, loss_metrics = _model_loss( model, inputs_batch, targets_batch, sample_weights=sample_weights_batch, training=False) _, metrics_results = _eager_metrics_fn(model, loss_outs, targets_batch) batch_outs = [] for _, v in zip(model.metrics_names, [backend.mean(loss)] + loss_metrics + metrics_results): batch_outs.append(tensor_util.constant_value(v)) if isinstance(batch_outs, list): if batch_index == 0: for batch_out in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): outs[i] += batch_out * len(batch_ids) else: if batch_index == 0: outs.append(0.) outs[0] += batch_outs * len(batch_ids) if verbose == 1: progbar.update(batch_end) for i in range(len(outs)): outs[i] /= num_samples if len(outs) == 1: return outs[0] return outs
def predict_loop(model, inputs, batch_size=32, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: inputs: List of input arrays. batch_size: integer batch size. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring `_predict_loop` finished. Ignored with the default value of `None`. Returns: Array of predictions (if the model has a single output) or list of arrays of predictions (if the model has multiple outputs). """ with backend.learning_phase_scope(0): num_samples = training_utils.check_num_samples( inputs, batch_size, steps, 'steps') if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) outs = [] batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] inputs_batch = slice_arrays(inputs, batch_ids) inputs_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) for val in inputs_batch] if len(inputs_batch) == 1: if model._expects_training_arg: batch_outs = model.call(inputs_batch[0], training=False) else: batch_outs = model.call(inputs_batch[0]) else: if model._expects_training_arg: batch_outs = model.call(inputs_batch, training=False) else: batch_outs = model.call(inputs_batch) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if batch_index == 0: # Pre-allocate the results arrays. for batch_out in batch_outs: dims = batch_out.shape[1:].dims dims_list = [d.value for d in dims] shape = (num_samples,) + tuple(dims_list) outs.append(np.zeros(shape, dtype=batch_out.dtype.as_numpy_dtype)) for i, batch_out in enumerate(batch_outs): outs[i][batch_start:batch_end] = batch_out if verbose == 1: progbar.update(batch_end) if len(outs) == 1: return outs[0] return outs
def fit_loop( model, inputs, targets, sample_weights=None, val_inputs=None, val_targets=None, val_sample_weights=None, batch_size=None, epochs=100, verbose=1, callbacks=None, shuffle=True, callback_metrics=None, initial_epoch=0, steps_per_epoch=None, validation_steps=None): """Abstract fit function for eager execution. Arguments: model: Instance of the model that is being executed in Eager mode. inputs: List of input arrays. targets: List of target arrays. sample_weights: Optional list of sample weight arrays. val_inputs: Input data for validation. val_targets: Target data for validation. val_sample_weights: Sample weight data for validation. batch_size: Integer batch size or None if unknown. epochs: Number of times to iterate over the data verbose: Verbosity mode, 0, 1 or 2 callbacks: List of callbacks to be called during training shuffle: Whether to shuffle the data at the beginning of each epoch callback_metrics: List of strings, the display names of the metrics passed to the callbacks. They should be the concatenation of list the display names of the outputs of `f` and the list of display names of the outputs of `f_val`. initial_epoch: Epoch at which to start training (useful for resuming a previous training run) steps_per_epoch: Total number of steps (batches of samples) before declaring one epoch finished and starting the next epoch. Ignored with the default value of `None`. validation_steps: Number of steps to run validation for (only if doing validation from data tensors). Ignored with default value of `None`. Returns: `History` object. Raises: ValueError: In case of invalid argument values. """ # Required for Eager mode with backend.learning_phase_scope(1): do_validation = False if val_inputs: do_validation = True if (verbose and inputs and hasattr(inputs[0], 'shape') and hasattr(val_inputs[0], 'shape')): print('Train on %d samples, validate on %d samples' % (inputs[0].shape[0], val_inputs[0].shape[0])) if validation_steps: if steps_per_epoch is None: raise ValueError('Can only use `validation_steps` when doing step-wise ' 'training, i.e. `steps_per_epoch` must be set.') do_validation = True out_labels = model.metrics_names if do_validation: callback_metrics = copy.copy(out_labels) + [ 'val_' + n for n in out_labels ] else: callback_metrics = copy.copy(out_labels) if sample_weights: feed_data = inputs + targets + sample_weights else: feed_data = inputs + targets num_train_samples = training_utils.check_num_samples( feed_data, batch_size=batch_size, steps=steps_per_epoch, steps_name='steps_per_epoch') if num_train_samples is not None: index_array = np.arange(num_train_samples) model.history = cbks.History() callbacks = [cbks.BaseLogger()] + (callbacks or []) + [model.history] if verbose: if steps_per_epoch is not None: count_mode = 'steps' else: count_mode = 'samples' callbacks += [cbks.ProgbarLogger(count_mode)] callbacks = cbks.CallbackList(callbacks) # it's possible to callback a different model than self # (used by Sequential models) if hasattr(model, 'callback_model') and model.callback_model: callback_model = model.callback_model else: callback_model = model callbacks.set_model(callback_model) callbacks.set_params({ 'batch_size': batch_size, 'epochs': epochs, 'steps': steps_per_epoch, 'samples': num_train_samples, 'verbose': verbose, 'do_validation': do_validation, 'metrics': callback_metrics or [], }) callbacks.on_train_begin() callback_model.stop_training = False for cbk in callbacks: if not val_inputs: cbk.validation_data = [] elif val_sample_weights: cbk.validation_data = val_inputs + val_targets + val_sample_weights else: cbk.validation_data = val_inputs + val_targets for epoch in range(initial_epoch, epochs): callbacks.on_epoch_begin(epoch) epoch_logs = {} if shuffle == 'batch': index_array = model._batch_shuffle(index_array, batch_size) elif shuffle: np.random.shuffle(index_array) batches = make_batches(num_train_samples, batch_size) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] try: inputs_batch = slice_arrays(inputs, batch_ids) targets_batch = slice_arrays(targets, batch_ids) if sample_weights: sample_weights_batch = slice_arrays(sample_weights, batch_ids) else: sample_weights_batch = None except TypeError: raise TypeError('TypeError while preparing batch. ' 'If using HDF5 input data, ' 'pass shuffle="batch".') batch_logs = {} batch_logs['batch'] = batch_index batch_logs['size'] = len(batch_ids) callbacks.on_batch_begin(batch_index, batch_logs) inputs_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) for val in inputs_batch] targets_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) for val in targets_batch] if sample_weights: sample_weights_batch = [ ops.convert_to_tensor(val, dtype=backend.floatx()) if val is not None else None for val in sample_weights_batch] outs, loss, loss_metrics = _process_single_batch( model, inputs_batch, targets_batch, sample_weights=sample_weights_batch, training=True) if not isinstance(outs, list): outs = [outs] for l, o in zip(out_labels, outs): batch_logs[l] = o # Required for Eager mode metrics_names, metrics_results = _eager_metrics_fn( model, outs, targets_batch) batch_logs['loss'] = tensor_util.constant_value(backend.mean(loss)) # TODO(anjalisridhar): Move this to compile to avoid duplicate code. # In graph mode we set the metric names in compile. However in # Eager mode we calculate the metrics for each batch in fit_loop. # We could calculate the metric names and functions in compile. # This would avoid setting the callback parameters separately. # We need to do this for the first iteration alone for m in metrics_names: if m not in callback_metrics: callback_metrics.append(m) callbacks.set_params({ 'batch_size': batch_size, 'epochs': epochs, 'steps': steps_per_epoch, 'samples': num_train_samples, 'verbose': verbose, 'do_validation': do_validation, 'metrics': callback_metrics or [], }) for k, v in zip(model.metrics_names, [backend.mean(loss)] + loss_metrics + metrics_results): batch_logs[k] = tensor_util.constant_value(v) callbacks.on_batch_end(batch_index, batch_logs) if callback_model.stop_training: break if batch_index == len(batches) - 1: # Last batch. if do_validation: val_outs = test_loop( model, val_inputs, val_targets, sample_weights=val_sample_weights, batch_size=batch_size, verbose=0) if not isinstance(val_outs, list): val_outs = [val_outs] # Same labels assumed. for l, o in zip(out_labels, val_outs): epoch_logs['val_' + l] = o callbacks.on_epoch_end(epoch, epoch_logs) if callback_model.stop_training: break callbacks.on_train_end() return model.history
def predict_loop(model, ins, batch_size=32, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: ins: list of tensors to be fed to `f`. batch_size: integer batch size. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring `_predict_loop` finished. Ignored with the default value of `None`. Returns: Array of predictions (if the model has a single output) or list of arrays of predictions (if the model has multiple outputs). """ K.set_learning_phase(False) num_samples = model._check_num_samples(ins, batch_size, steps, 'steps') if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) outs = [] batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if ins and isinstance(ins[-1], float): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) ins_batch_converted = [] for ib in ins_batch: ins_batch_converted.append(ops.convert_to_tensor(ib, dtype=K.floatx())) eager_model_inputs = [] for i in range(len(model.inputs)): eager_model_inputs.append(ins_batch_converted[i]) if len(eager_model_inputs) == 1: batch_outs = model.call(eager_model_inputs[0]) else: batch_outs = model.call(eager_model_inputs) if not isinstance(batch_outs, list): batch_outs = [batch_outs] if batch_index == 0: # Pre-allocate the results arrays. for batch_out in batch_outs: dims = batch_out.shape[1:].dims dims_list = [d.value for d in dims] shape = (num_samples,) + tuple(dims_list) outs.append(np.zeros(shape, dtype=batch_out.dtype.as_numpy_dtype)) for i, batch_out in enumerate(batch_outs): outs[i][batch_start:batch_end] = batch_out if verbose == 1: progbar.update(batch_end) if len(outs) == 1: return outs[0] return outs
def test_loop(model, ins, batch_size=None, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Model instance that is being evaluated in Eager mode. ins: list of tensors to be fed to `f`. batch_size: integer batch size or `None`. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring predictions finished. Ignored with the default value of `None`. Returns: Scalar loss (if the model has a single output and no metrics) or list of scalars (if the model has multiple outputs and/or metrics). The attribute `model.metrics_names` will give you the display labels for the scalar outputs. """ K.set_learning_phase(False) num_samples = model._check_num_samples(ins, batch_size, steps, 'steps') outs = [] if verbose == 1: progbar = Progbar(target=num_samples) batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if isinstance(ins[-1], float): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) ins_batch_converted = [] for ib in ins_batch: ins_batch_converted.append(ops.convert_to_tensor(ib, dtype=K.floatx())) eager_model_inputs = [] eager_model_outputs = [] for i in range(len(model.inputs)): eager_model_inputs.append(ins_batch_converted[i]) for i in range(len(model.inputs), len(ins_batch_converted)): eager_model_outputs.append(ins_batch_converted[i]) loss_outs, loss, loss_metrics = _model_loss(model, eager_model_inputs, eager_model_outputs) _, metrics_results = _eager_metrics_fn(model, loss_outs, eager_model_outputs) batch_outs = [] for _, v in zip(model.metrics_names, [K.mean(loss)] + loss_metrics + metrics_results): batch_outs.append(tensor_util.constant_value(v)) if isinstance(batch_outs, list): if batch_index == 0: for batch_out in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): outs[i] += batch_out * len(batch_ids) else: if batch_index == 0: outs.append(0.) outs[0] += batch_outs * len(batch_ids) if verbose == 1: progbar.update(batch_end) for i in range(len(outs)): outs[i] /= num_samples if len(outs) == 1: return outs[0] return outs
def test_loop(model, inputs, targets, sample_weights=None, batch_size=None, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Keras Model instance. inputs: List of input arrays. targets: List of target arrays. sample_weights: Optional list of sample weight arrays. batch_size: integer batch size or `None`. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring predictions finished. Ignored with the default value of `None`. Returns: Scalar loss (if the model has a single output and no metrics) or list of scalars (if the model has multiple outputs and/or metrics). The attribute `model.metrics_names` will give you the display labels for the scalar outputs. """ model._make_test_function() f = model.test_function sample_weights = sample_weights or [] if model.uses_learning_phase and not isinstance(K.learning_phase(), int): ins = inputs + targets + sample_weights + [0] else: ins = inputs + targets + sample_weights if hasattr(model, 'metrics'): for m in model.metrics: if isinstance(m, Layer): m.reset_states() stateful_metric_indices = [ i for i, name in enumerate(model.metrics_names) if str(name) in model.stateful_metric_names ] else: stateful_metric_indices = [] num_samples = training_utils.check_num_samples(ins, batch_size, steps, 'steps') outs = [] if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) # To prevent a slowdown, we find beforehand the arrays that need conversion. feed = model._feed_inputs + model._feed_targets + model._feed_sample_weights indices_for_conversion_to_dense = [] for i in range(len(feed)): if issparse is not None and issparse( ins[i]) and not K.is_sparse(feed[i]): indices_for_conversion_to_dense.append(i) if steps is not None: for step in range(steps): batch_outs = f(ins) if isinstance(batch_outs, list): if step == 0: for _ in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): if i in stateful_metric_indices: outs[i] = batch_out else: outs[i] += batch_out else: if step == 0: outs.append(0.) outs[0] += batch_outs if verbose == 1: progbar.update(step + 1) for i in range(len(outs)): if i not in stateful_metric_indices: outs[i] /= steps else: batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if isinstance(ins[-1], int): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) for i in indices_for_conversion_to_dense: ins_batch[i] = ins_batch[i].toarray() batch_outs = f(ins_batch) if isinstance(batch_outs, list): if batch_index == 0: for batch_out in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): if i in stateful_metric_indices: outs[i] = batch_out else: outs[i] += batch_out * len(batch_ids) else: if batch_index == 0: outs.append(0.) outs[0] += batch_outs * len(batch_ids) if verbose == 1: progbar.update(batch_end) for i in range(len(outs)): if i not in stateful_metric_indices: outs[i] /= num_samples if len(outs) == 1: return outs[0] return outs
def test_loop(model, inputs, targets, sample_weights=None, batch_size=None, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Keras Model instance. inputs: List of input arrays. targets: List of target arrays. sample_weights: Optional list of sample weight arrays. batch_size: integer batch size or `None`. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring predictions finished. Ignored with the default value of `None`. Returns: Scalar loss (if the model has a single output and no metrics) or list of scalars (if the model has multiple outputs and/or metrics). The attribute `model.metrics_names` will give you the display labels for the scalar outputs. """ model._make_test_function() f = model.test_function sample_weights = sample_weights or [] if model.uses_learning_phase and not isinstance(K.learning_phase(), int): ins = inputs + targets + sample_weights + [0] else: ins = inputs + targets + sample_weights if hasattr(model, 'metrics'): for m in model.metrics: if isinstance(m, Layer): m.reset_states() stateful_metric_indices = [ i for i, name in enumerate(model.metrics_names) if str(name) in model.stateful_metric_names ] else: stateful_metric_indices = [] num_samples = training_utils.check_num_samples( ins, batch_size, steps, 'steps') outs = [] if verbose == 1: if steps is not None: progbar = Progbar(target=steps) else: progbar = Progbar(target=num_samples) # To prevent a slowdown, we find beforehand the arrays that need conversion. feed = model._feed_inputs + model._feed_targets + model._feed_sample_weights indices_for_conversion_to_dense = [] for i in range(len(feed)): if issparse is not None and issparse(ins[i]) and not K.is_sparse(feed[i]): indices_for_conversion_to_dense.append(i) if steps is not None: for step in range(steps): batch_outs = f(ins) if isinstance(batch_outs, list): if step == 0: for _ in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): if i in stateful_metric_indices: outs[i] = batch_out else: outs[i] += batch_out else: if step == 0: outs.append(0.) outs[0] += batch_outs if verbose == 1: progbar.update(step + 1) for i in range(len(outs)): if i not in stateful_metric_indices: outs[i] /= steps else: batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if isinstance(ins[-1], int): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) for i in indices_for_conversion_to_dense: ins_batch[i] = ins_batch[i].toarray() batch_outs = f(ins_batch) if isinstance(batch_outs, list): if batch_index == 0: for batch_out in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): if i in stateful_metric_indices: outs[i] = batch_out else: outs[i] += batch_out * len(batch_ids) else: if batch_index == 0: outs.append(0.) outs[0] += batch_outs * len(batch_ids) if verbose == 1: progbar.update(batch_end) for i in range(len(outs)): if i not in stateful_metric_indices: outs[i] /= num_samples if len(outs) == 1: return outs[0] return outs
def fit_loop(model, inputs, targets, sample_weights=None, batch_size=None, epochs=100, verbose=1, callbacks=None, val_inputs=None, val_targets=None, val_sample_weights=None, shuffle=True, callback_metrics=None, initial_epoch=0, steps_per_epoch=None, validation_steps=None): """Abstract fit function for arrays of data. Arguments: model: Keras Model instance. inputs: List of input arrays. targets: List of target arrays. sample_weights: Optional list of sample weight arrays. batch_size: Integer batch size or None if unknown. epochs: Number of times to iterate over the data verbose: Verbosity mode, 0, 1 or 2 callbacks: List of callbacks to be called during training val_inputs: List of input arrays. val_targets: List of target arrays. val_sample_weights: Optional list of sample weight arrays. shuffle: Whether to shuffle the data at the beginning of each epoch callback_metrics: List of strings, the display names of the metrics passed to the callbacks. They should be the concatenation of list the display names of the outputs of `f` and the list of display names of the outputs of `f_val`. initial_epoch: Epoch at which to start training (useful for resuming a previous training run) steps_per_epoch: Total number of steps (batches of samples) before declaring one epoch finished and starting the next epoch. Ignored with the default value of `None`. validation_steps: Number of steps to run validation for (only if doing validation from data tensors). Ignored with the default value of `None`. Returns: `History` object. Raises: ValueError: in case of invalid arguments. """ model._make_train_function() f = model.train_function sample_weights = sample_weights or [] val_sample_weights = val_sample_weights or [] if model.uses_learning_phase and not isinstance(K.learning_phase(), int): ins = inputs + targets + sample_weights + [1] if val_inputs: val_ins = val_inputs + val_targets + val_sample_weights + [1] else: ins = inputs + targets + sample_weights if val_inputs: val_ins = val_inputs + val_targets + val_sample_weights if not val_inputs: val_ins = [] do_validation = False if val_inputs: do_validation = True if verbose and inputs and hasattr(inputs[0], 'shape') and hasattr( val_inputs[0], 'shape'): print('Train on %d samples, validate on %d samples' % (inputs[0].shape[0], val_inputs[0].shape[0])) if validation_steps: do_validation = True if steps_per_epoch is None: raise ValueError('Can only use `validation_steps` ' 'when doing step-wise ' 'training, i.e. `steps_per_epoch` ' 'must be set.') out_labels = model.metrics_names if do_validation: callback_metrics = copy.copy(out_labels) + [ 'val_' + n for n in out_labels ] else: callback_metrics = copy.copy(out_labels) num_train_samples = training_utils.check_num_samples( ins, batch_size, steps_per_epoch, 'steps_per_epoch') if num_train_samples is not None: index_array = np.arange(num_train_samples) model.history = cbks.History() all_callbacks = [ cbks.BaseLogger(stateful_metrics=model.stateful_metric_names) ] if verbose: if steps_per_epoch is not None: count_mode = 'steps' else: count_mode = 'samples' all_callbacks.append( cbks.ProgbarLogger(count_mode, stateful_metrics=model.stateful_metric_names)) all_callbacks += (callbacks or []) + [model.history] callbacks = cbks.CallbackList(all_callbacks) out_labels = out_labels or [] # it's possible to callback a different model than self # (used by Sequential models) if hasattr(model, 'callback_model') and model.callback_model: callback_model = model.callback_model else: callback_model = model callbacks.set_model(callback_model) callbacks.set_params({ 'batch_size': batch_size, 'epochs': epochs, 'steps': steps_per_epoch, 'samples': num_train_samples, 'verbose': verbose, 'do_validation': do_validation, 'metrics': callback_metrics or [], }) callbacks.on_train_begin() callback_model.stop_training = False for cbk in callbacks: cbk.validation_data = val_ins # To prevent a slowdown, we find beforehand the arrays that need conversion. feed = model._feed_inputs + model._feed_targets + model._feed_sample_weights indices_for_conversion_to_dense = [] for i in range(len(feed)): if issparse is not None and issparse( ins[i]) and not K.is_sparse(feed[i]): indices_for_conversion_to_dense.append(i) for epoch in range(initial_epoch, epochs): # Reset stateful metrics for m in model.metrics: if isinstance(m, Layer): m.reset_states() # Update callbacks callbacks.on_epoch_begin(epoch) epoch_logs = {} if steps_per_epoch is not None: for step_index in range(steps_per_epoch): batch_logs = {} batch_logs['batch'] = step_index batch_logs['size'] = 1 callbacks.on_batch_begin(step_index, batch_logs) try: outs = f(ins) except errors.OutOfRangeError: logging.warning( 'Your dataset iterator ran out of data; ' 'interrupting training. Make sure that your dataset ' 'can generate at least `steps_per_epoch * epochs` ' 'batches (in this case, %d batches).' % steps_per_epoch * epochs) break if not isinstance(outs, list): outs = [outs] for l, o in zip(out_labels, outs): batch_logs[l] = o callbacks.on_batch_end(step_index, batch_logs) if callback_model.stop_training: break if do_validation: val_outs = test_loop(model, val_inputs, val_targets, sample_weights=val_sample_weights, batch_size=batch_size, steps=validation_steps, verbose=0) if not isinstance(val_outs, list): val_outs = [val_outs] # Same labels assumed. for l, o in zip(out_labels, val_outs): epoch_logs['val_' + l] = o else: if shuffle == 'batch': index_array = training_utils.batch_shuffle( index_array, batch_size) elif shuffle: np.random.shuffle(index_array) batches = make_batches(num_train_samples, batch_size) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] try: if isinstance(ins[-1], int): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) except TypeError: raise TypeError('TypeError while preparing batch. ' 'If using HDF5 input data, ' 'pass shuffle="batch".') batch_logs = {} batch_logs['batch'] = batch_index batch_logs['size'] = len(batch_ids) callbacks.on_batch_begin(batch_index, batch_logs) for i in indices_for_conversion_to_dense: ins_batch[i] = ins_batch[i].toarray() outs = f(ins_batch) if not isinstance(outs, list): outs = [outs] for l, o in zip(out_labels, outs): batch_logs[l] = o callbacks.on_batch_end(batch_index, batch_logs) if callback_model.stop_training: break if batch_index == len(batches) - 1: # Last batch. if do_validation: val_outs = test_loop(model, val_inputs, val_targets, sample_weights=val_sample_weights, batch_size=batch_size, verbose=0) if not isinstance(val_outs, list): val_outs = [val_outs] # Same labels assumed. for l, o in zip(out_labels, val_outs): epoch_logs['val_' + l] = o callbacks.on_epoch_end(epoch, epoch_logs) if callback_model.stop_training: break callbacks.on_train_end() return model.history
def test_loop(model, ins, batch_size=None, verbose=0, steps=None): """Abstract method to loop over some data in batches. Arguments: model: Model instance that is being evaluated in Eager mode. ins: list of tensors to be fed to `f`. batch_size: integer batch size or `None`. verbose: verbosity mode. steps: Total number of steps (batches of samples) before declaring predictions finished. Ignored with the default value of `None`. Returns: Scalar loss (if the model has a single output and no metrics) or list of scalars (if the model has multiple outputs and/or metrics). The attribute `model.metrics_names` will give you the display labels for the scalar outputs. """ K.set_learning_phase(False) num_samples = model._check_num_samples(ins, batch_size, steps, 'steps') outs = [] if verbose == 1: progbar = Progbar(target=num_samples) batches = make_batches(num_samples, batch_size) index_array = np.arange(num_samples) for batch_index, (batch_start, batch_end) in enumerate(batches): batch_ids = index_array[batch_start:batch_end] if isinstance(ins[-1], float): # Do not slice the training phase flag. ins_batch = slice_arrays(ins[:-1], batch_ids) + [ins[-1]] else: ins_batch = slice_arrays(ins, batch_ids) ins_batch_converted = [] for ib in ins_batch: ins_batch_converted.append( ops.convert_to_tensor(ib, dtype=K.floatx())) eager_model_inputs = [] eager_model_outputs = [] for i in range(len(model.inputs)): eager_model_inputs.append(ins_batch_converted[i]) for i in range(len(model.inputs), len(ins_batch_converted)): eager_model_outputs.append(ins_batch_converted[i]) loss_outs, loss, loss_metrics = _model_loss(model, eager_model_inputs, eager_model_outputs, training=False) _, metrics_results = _eager_metrics_fn(model, loss_outs, eager_model_outputs) batch_outs = [] for _, v in zip(model.metrics_names, [K.mean(loss)] + loss_metrics + metrics_results): batch_outs.append(tensor_util.constant_value(v)) if isinstance(batch_outs, list): if batch_index == 0: for batch_out in enumerate(batch_outs): outs.append(0.) for i, batch_out in enumerate(batch_outs): outs[i] += batch_out * len(batch_ids) else: if batch_index == 0: outs.append(0.) outs[0] += batch_outs * len(batch_ids) if verbose == 1: progbar.update(batch_end) for i in range(len(outs)): outs[i] /= num_samples if len(outs) == 1: return outs[0] return outs