def accuracy_length(y_true, y_pred):
"""Compute the length control signal accuracy by matching position of EOS token."""
EOS_token = 2
mask_PAD = K.all(K.equal(y_true, 0), axis=-1) # Shape = (N, max_length, 1)
mask_PAD = 1 - K.cast(mask_PAD, K.floatx())
mask_PAD = tf.squeeze(
mask_PAD) # Shape = (N, max_length). False if this is PAD.
y_pred = K.cast(K.argmax(y_pred, axis=-1), K.floatx())
y_pred = y_pred * mask_PAD # Shape = (N, max_length)
filter_EOS = K.all(K.equal(y_true, EOS_token), axis=-1)
filter_EOS = K.cast(filter_EOS, K.floatx())
filter_EOS = tf.squeeze(
filter_EOS) # Shape = (N, max_length), True if it is EOS.
y_expected = K.equal(y_pred * filter_EOS, float(EOS_token))
y_expected = K.cast(y_expected, K.floatx()) # Shape = (N, max_length)
y_expected = K.sum(y_expected, axis=-1) # Shape = (N, )
y_expected = K.cast((K.equal(y_expected, 1.0)), K.floatx())
y_result = K.cast(K.equal(y_pred, float(EOS_token)),
K.floatx()) # Shape = (N, max_length)
y_result = K.sum(y_result, axis=-1) # Shape = (N, )
y_result = K.cast((K.equal(y_result, 1.0)), K.floatx())
accuracy = y_expected * y_result # Shape = (N, )
accuracy = (K.sum(accuracy) / K.sum(filter_EOS)
) # / K.sum(tf.ones_like(accu)))
return accuracy
def competition_coef(y_true, y_pred, smooth=1):
y_pred = K.argmax(y_pred, axis=-1)
y_true = K.argmax(y_true, axis=-1)
# try:
# Compute tumor+kidney Dice
tk_pd = K.greater(y_pred, 0)
tk_gt = K.greater(y_true, 0)
intersection = K.all(K.stack([tk_gt, tk_pd], axis=3), axis=3)
tk_dice = (2 * K.sum(K.cast(intersection, K.floatx())) + smooth)/ (
K.sum(K.cast(tk_pd, K.floatx())) + K.sum(K.cast(tk_gt, K.floatx())) + smooth
)
# except ZeroDivisionError:
# return 0
# try:
# Compute tumor Dice
tu_pd = K.greater(y_pred, 1)
tu_gt = K.greater(y_true, 1)
intersection = K.all(K.stack([tu_pd, tu_gt], axis=3), axis=3)
tu_dice = (2 * K.sum(K.cast(intersection, K.floatx())) + smooth)/ (
K.sum(K.cast(tu_pd, K.floatx())) + K.sum(K.cast(tu_gt, K.floatx())) + smooth
)
# except ZeroDivisionError:
# return tk_dice / 2.0
return (tk_dice+tu_dice) / 2.0
def basic_loss(self, y_true, y_pred, go_backwards=False):
"""y_true需要是整数形式（非one hot）
"""
# 导出mask并转换数据类型
mask = K.all(K.greater(y_pred, -1e6), axis=2)
mask = K.cast(mask, K.floatx())
# y_true需要重新明确一下shape和dtype
y_true = K.reshape(y_true, K.shape(y_pred)[:-1])
y_true = K.cast(y_true, 'int32')
# 反转相关
if self.hidden_dim is None:
if go_backwards: # 是否反转序列
y_true, y_pred = self.reverse_sequence([y_true, y_pred], mask)
trans = K.transpose(self.trans)
else:
trans = self.trans
histoty = K.gather(trans, y_true)
else:
if go_backwards: # 是否反转序列
y_true, y_pred = self.reverse_sequence([y_true, y_pred], mask)
r_trans, l_trans = self.l_trans, self.r_trans
else:
l_trans, r_trans = self.l_trans, self.r_trans
histoty = K.gather(l_trans, y_true)
histoty = tf.einsum('bnd,kd->bnk', histoty, r_trans)
# 计算loss
histoty = K.concatenate([y_pred[:, :1], histoty[:, :-1]], 1)
y_pred = (y_pred + histoty) / 2
loss = K.sparse_categorical_crossentropy(
y_true, y_pred, from_logits=True
)
return K.sum(loss * mask) / K.sum(mask)
def basic_accuracy(self, y_true, y_pred, go_backwards=False):
"""训练过程中显示逐帧准确率的函数，排除了mask的影响
此处y_true需要是整数形式（非one hot）
"""
# 导出mask并转换数据类型
mask = K.all(K.greater(y_pred, -1e6), axis=2)
mask = K.cast(mask, K.floatx())
# y_true需要重新明确一下shape和dtype
y_true = K.reshape(y_true, K.shape(y_pred)[:-1])
y_true = K.cast(y_true, 'int32')
# 反转相关
if self.hidden_dim is None:
if go_backwards: # 是否反转序列
y_true, y_pred = self.reverse_sequence([y_true, y_pred], mask)
trans = K.transpose(self.trans)
else:
trans = self.trans
histoty = K.gather(trans, y_true)
else:
if go_backwards: # 是否反转序列
y_true, y_pred = self.reverse_sequence([y_true, y_pred], mask)
r_trans, l_trans = self.l_trans, self.r_trans
else:
l_trans, r_trans = self.l_trans, self.r_trans
histoty = K.gather(l_trans, y_true)
histoty = tf.einsum('bnd,kd->bnk', histoty, r_trans)
# 计算逐标签accuracy
histoty = K.concatenate([y_pred[:, :1], histoty[:, :-1]], 1)
y_pred = (y_pred + histoty) / 2
y_pred = K.cast(K.argmax(y_pred, 2), 'int32')
isequal = K.cast(K.equal(y_true, y_pred), K.floatx())
return K.sum(isequal * mask) / K.sum(mask)
def dense_loss(self, y_true, y_pred):
"""y_true需要是one hot形式
"""
# 导出mask并转换数据类型
# [B, T, 1] 这里也就是看 这个 T 是否是 pad 的
mask = K.all(K.greater(y_pred, -1e6), axis=2, keepdims=True)
mask = K.cast(mask, K.floatx())
# 计算目标分数
y_true, y_pred = y_true * mask, y_pred * mask
target_score = self.target_score(y_true, y_pred)
# 递归计算log Z
init_states = [y_pred[:, 0]]
# [B, T, output_dim] [B, T, 1] -> [B, T, output_dim+1]
# 这里是为了传递 mask 到 rnn 中
y_pred = K.concatenate([y_pred, mask], axis=2)
input_length = K.int_shape(y_pred[:, 1:])[1]
# 这里会把 y_pred[:, 1:] 在 time 维度 split 开 一个个继续迭代计算
log_norm, _, _ = K.rnn(
self.log_norm_step,
y_pred[:, 1:],
init_states,
input_length=input_length
) # 最后一步的log Z向量
log_norm = tf.reduce_logsumexp(log_norm, 1) # logsumexp得标量
# 计算损失 -log p
return log_norm - target_score
def _compute_valid_seed_region(self):
positions = K.concatenate([
K.expand_dims(K.tile(K.expand_dims(K.arange(self.height), axis=1),
[1, self.width]),
axis=-1),
K.expand_dims(K.tile(K.expand_dims(K.arange(self.width), axis=0),
[self.height, 1]),
axis=-1),
],
axis=-1)
half_block_size = self.block_size // 2
valid_seed_region = K.switch(
K.all(
K.stack(
[
positions[:, :, 0] >= half_block_size,
positions[:, :, 1] >= half_block_size,
positions[:, :, 0] < self.height - half_block_size,
positions[:, :, 1] < self.width - half_block_size,
],
axis=-1,
),
axis=-1,
),
self.ones,
self.zeros,
)
return K.expand_dims(K.expand_dims(valid_seed_region, axis=0), axis=-1)
def custom_loss(y_true, y_pred):
y_true_label_1 = y_true[:, :num_classes]
y_true_label_2 = y_true[:, num_classes:num_classes * 2]
y_pred_label_1 = y_pred[:, :num_classes]
y_pred_label_2 = y_pred[:, num_classes:num_classes * 2]
y_pred_embedding_1 = y_pred[:,
num_classes * 2:num_classes * 2 + emb_size]
y_pred_embedding_2 = y_pred[:, num_classes * 2 + emb_size:]
class_loss_1 = categorical_crossentropy(y_true_label_1, y_pred_label_1)
class_loss_2 = categorical_crossentropy(y_true_label_2, y_pred_label_2)
embedding_loss = cosine_similarity(y_pred_embedding_1,
y_pred_embedding_2)
are_labels_equal = K.all(K.equal(y_true_label_1, y_true_label_2),
axis=1)
a = tf.where(are_labels_equal,
tf.fill([tf.shape(are_labels_equal)[0]], 1.0),
tf.fill([tf.shape(are_labels_equal)[0]], -1.0))
result = class_loss_1 + class_loss_2 + tf.math.multiply(
a, embedding_loss)
return tf.math.reduce_mean(result)
def masked_categorical_crossentropy(y_true, y_pred):
mask = K.all(K.equal(y_true, mask_value), axis=-1)
mask = 1 - K.cast(mask, K.floatx())
loss = K.categorical_crossentropy(y_true, y_pred) * mask
return K.sum(loss) / K.sum(mask)
def accperclass(y_true, y_pred, c):
''' Returns the accuracy per class for the class c'''
z = K.equal(
K.reshape(K.cast(K.argmax(y_pred), 'float32'), K.shape(y_true)),
y_true)
e = K.equal(y_true, c)
return (K.sum(K.cast(K.all(K.stack([z, e], axis=0), axis=0), 'int32')) /
K.maximum(1, K.sum(K.cast(e, 'int32'))))
def joint_histogram(tensor, bins):
_uniq_obj = np.zeros((bins, bins, 2, 1))
for i in range(bins):
for j in range(bins):
_uniq_obj[i, j, :, 0] = np.array([i, j])
_uniq_obj = K.constant(_uniq_obj)
_cond = K.all(K.equal(tensor, _uniq_obj), axis=2)
return tf.count_nonzero(_cond, axis=2)
def full_number_accuracy(y_true, y_pred):
y_true_argmax = K.argmax(y_true)
y_pred_argmax = K.argmax(y_pred)
tfd = K.equal(y_true_argmax, y_pred_argmax)
tfn = K.all(tfd, axis=1)
tfc = K.cast(tfn, dtype='float32')
tfm = K.mean(tfc)
return tfm
def compute_mask(self, inputs, mask=None): if self.conditional: masks = [K.expand_dims(m, 0) for m in mask if m is not None] if len(masks) == 0: return None else: return K.all(K.concatenate(masks, axis=0), axis=0) else: return mask
def soft_acc_multi_output(y_true, y_pred):
return K.mean(
K.all(
K.equal(
K.cast(K.round(y_true), "int32"), K.cast(K.round(y_pred), "int32"),
),
axis=1,
)
)
def compute_mask(self, inputs, mask=None):
if self.conditional:
masks = mask if mask is not None else []
masks = [m[None] for m in masks if m is not None]
if len(masks) == 0:
return None
else:
return K.all(K.concatenate(masks, axis=0), axis=0)
else:
return mask
def pl_categorical_accuracy(self, y_true, y_pred):
index = y_true == self.unlabeled
index = K.all(index, axis=1)
acc = keras.metrics.categorical_accuracy(y_true, y_pred)
# tf.print('acc', acc.shape, 'index', index.shape)
# return tf.reduce_mean(acc, axis=-1)
return tf.reduce_sum(tf.where(index, 0.0, acc), axis=-1) / tf.cast(
tf.reduce_sum(tf.where(index, 0, 1), axis=-1), tf.float32)
def masked_perplexity_loss(y_true, y_pred, PAD_token=0):
"""Construct customer masked perplexity loss."""
mask = K.all(K.equal(y_true, PAD_token),
axis=-1) # Label padding as zero in y_true
mask = 1 - K.cast(mask, K.floatx())
nomask = K.sum(mask)
loss = K.sparse_categorical_crossentropy(
y_true,
y_pred) * mask # Multiply categorical_crossentropy with the mask
return tf.exp(K.sum(loss) / nomask)
def viterbi_accuracy(y_true, y_pred):
# -1e10 to avoid zero at sum(mask)
mask = K.cast(K.all(K.greater(y_pred, -1e10), axis=2), K.floatx())
shape = tf.shape(y_pred)
sequence_lengths = tf.ones(shape[0], dtype=tf.int32) * (shape[1])
y_pred, _ = crf_decode(y_pred, self.transitions, sequence_lengths)
if self.sparse_target:
y_true = K.argmax(y_true, 2)
y_pred = K.cast(y_pred, 'int32')
y_true = K.cast(y_true, 'int32')
corrects = K.cast(K.equal(y_true, y_pred), K.floatx())
return K.sum(corrects * mask) / K.sum(mask)
def acc_igm1(y_true, y_pred):
"""
custom accuracy function which only considers known-labels(not -1)
"""
known = K.equal(
K.max(y_true, axis=-1),
1) # if max value == 0, it means -1 (unknown) label.
correct = K.equal(K.argmax(y_true, axis=-1),
K.argmax(y_pred, axis=-1))
true = K.all(K.stack([correct, known], axis=0), axis=0)
return K.sum(K.cast(true, 'int32')) / K.sum(K.cast(known, 'int32'))
def sentence_accuracy(y_true, y_pred):
y_true_class = K.argmax(y_true, axis=-1)
y_pred_class = K.argmax(y_pred, axis=-1)
ignore_mask = K.cast(K.equal(y_true_class, to_ignore), 'int32')
matches = K.cast(K.equal(y_true_class, y_pred_class), 'int32')
matches = K.any(K.stack([matches, ignore_mask], axis=0),
axis=0) # This is logic OR
accuracy = K.sum(K.cast(K.all(matches, axis=1), 'int32')) / K.sum(
K.cast(K.any(matches, axis=1), 'int32'))
return accuracy
def plate_acc(y_true, y_pred):
'''
How many plates were correctly classified
If Ground Truth is ABC 123
Then prediction ABC 123 would score 1
else ABD 123 would score 0
Avg these results (1 + 0) / 2 -> Gives .5 accuracy
(Half of the plates were completely corrected classified)
'''
y_true = K.reshape(y_true, shape=(-1, 7, 37))
y_pred = K.reshape(y_pred, shape=(-1, 7, 37))
et = K.equal(K.argmax(y_true), K.argmax(y_pred))
return K.mean(K.cast(K.all(et, axis=-1, keepdims=False), dtype='float32'))
def sparse_accuracy(self, y_true, y_pred): """训练过程中显示逐帧准确率的函数，排除了mask的影响 此处y_true需要是整数形式（非one hot） """ # 导出mask并转换数据类型 mask = K.all(K.greater(y_pred, -1e6), axis=2) mask = K.cast(mask, K.floatx()) # y_true需要重新明确一下shape和dtype y_true = K.reshape(y_true, K.shape(y_pred)[:-1]) y_true = K.cast(y_true, 'int32') # 逐标签取最大来粗略评测训练效果 y_pred = K.cast(K.argmax(y_pred, 2), 'int32') isequal = K.cast(K.equal(y_true, y_pred), K.floatx()) return K.sum(isequal * mask) / K.sum(mask)
def rec_acc(y_true, y_pred):
# y_true: (batch_size, maxlen, 1)
# y_pred: (batch_size, maxlen, 1)
# (batch_size, maxlen, 1)
is_particle_wise_equal = K.equal(y_true, K.round(y_pred))
# (batch_size, maxlen)
is_particle_wise_equal = K.squeeze(is_particle_wise_equal, axis=-1)
# (batch_size, )
is_jet_wise_correct = K.all(is_particle_wise_equal, axis=1)
return K.mean(is_jet_wise_correct)
def precision(y_true, y_pred):
"""Precision for foreground pixels.
Calculates pixelwise precision TP/(TP + FP).
"""
# count true positives
truth = K.round(K.clip(y_true, K.epsilon(), 1))
pred_pos = K.round(K.clip(y_pred, K.epsilon(), 1))
true_pos = K.sum(K.cast(K.all(K.stack([truth, pred_pos], axis=2), axis=2),
dtype='float64'))
pred_pos_ct = K.sum(pred_pos) + K.epsilon()
precision = true_pos/pred_pos_ct
return precision
def pl_loss_test(self, y_true, y_pred):
pl = K.one_hot(K.argmax(y_pred), self.out_size)
pl = tf.cast(pl, y_true.dtype)
index = y_true == self.unlabeled
y_pl = tf.where(index, pl, y_true)
index = K.all(index, axis=1)
# coef_arr = tf.where(index, self.alpha, 1.0)
loss = keras.losses.categorical_crossentropy(y_pl, y_pred)
labeled_loss = tf.reduce_sum(tf.where(index, 0, loss))
unlabeled_loss = tf.reduce_sum(tf.where(index, loss, 0))
return labeled_loss + self.alpha * unlabeled_loss
def recall(y_true, y_pred):
"""Precision for foreground pixels.
Calculates pixelwise recall TP/(TP + FN).
"""
# count true positives
truth = K.round(K.clip(y_true, K.epsilon(), 1))
pred_pos = K.round(K.clip(y_pred, K.epsilon(), 1))
true_pos = K.sum(K.cast(K.all(K.stack([truth, pred_pos], axis=2), axis=2),
dtype='float64'))
truth_ct = K.sum(K.round(K.clip(y_true, K.epsilon(), 1)))
if truth_ct == 0:
return 0
recall = true_pos/truth_ct
return recall
def _compute_valid_seed_region(self):
positions = K.arange(self.seq_len)
half_block_size = self.block_size // 2
valid_seed_region = K.switch(
K.all(
K.stack(
[
positions >= half_block_size,
positions < self.seq_len - half_block_size,
],
axis=-1,
),
axis=-1,
),
self.ones,
self.zeros,
)
return K.expand_dims(K.expand_dims(valid_seed_region, axis=0), axis=-1)
def pl_loss(self, y_true, y_pred):
# tf.print('loss for:', y_true.shape, y_pred.shape, y_true[0])
'''
Custom loss function for pseudo-labeling
In general, I believe that this is only well-defined when y is 1D and one-hot encoded
unlabeled = scalar of what value has been assigned to the unlabled samples
num_classes = number of classes of Y
alpha = alpha term of conditional cross-entropy
'''
# tf.print('pl_loss:', y_true, y_pred)
pl = K.one_hot(K.argmax(y_pred), self.out_size)
pl = tf.cast(pl, y_true.dtype)
# Calculate whether each sample in the batch is labeled or unlabeled
index = y_true == self.unlabeled
# clip the predictions for numerical stability
# pred = K.clip(y_pred, 1e-12, 1 - 1e-12)
# tf.print('y_pred', y_pred.shape, y_pred)
# tf.print('y_pl', pl.shape, pl)
# tf.print('y_true', y_true.shape, y_true)
# tf.print('index', index.shape, index)
y_pl = tf.where(index, pl, y_true)
# tf.print('y_pl', y_pl.shape, y_pl)
# tf.print('index', index.shape, index)
# Set coefficient for each sample based on whether labeled or unlabeled
index = K.all(index, axis=1)
coef_arr = tf.where(index, self.alpha, 1.0)
# tf.print(self.alpha)
# tf.print('coef_arr', coef_arr.shape, coef_arr)
# compute the loss
loss = keras.losses.categorical_crossentropy(y_pl, y_pred)
# tf.print('loss', loss.shape, loss)
# loss = tf.nn.softmax_cross_entropy_with_logits(y_true, y_pred)
# tf.print(tf.reduce_sum(coef_arr * loss))
return tf.reduce_sum(coef_arr * loss)
def discretize_with_histogram(tensor, bins):
_min = K.min(tensor)
_max = K.max(tensor)
_len_shape = len(tensor.shape)
_bins = K.cast(tf.range(bins), dtype=K.floatx())
_range = tf.linspace(_min, _max, bins + 1)
for _ in range(_len_shape):
_bins = K.expand_dims(_bins, axis=-1)
_range = K.expand_dims(_range, axis=-1)
_cond1 = K.greater_equal(tensor, _range[:-1])
_cond2 = K.less(tensor, _range[1:])
_cond3 = K.less_equal(tensor, _range[1:])
_cond4 = K.concatenate((_cond2[:-1], _cond3[-1:]), axis=0)
_all_cond = K.cast(K.all(K.stack((_cond1, _cond4), axis=0), axis=0),
dtype=K.floatx())
_axis = tuple([i + 1 for i in range(_len_shape)])
_discrete = K.sum(_all_cond * _bins, axis=0)
_histogram = tf.count_nonzero(_all_cond, axis=_axis)
return _discrete, _histogram
def get_updates(self, loss, params):
# Only for initialization (仅初始化)
self.optimizer.get_updates(loss, params)
# Common updates (常规更新)
dense_params = [p for p in params if p not in self.embeddings]
self.updates = self.optimizer.get_updates(loss, dense_params)
# Sparse update (稀疏更新)
sparse_params = self.embeddings
sparse_grads = self.get_gradients(loss, sparse_params)
sparse_flags = [
K.all(K.not_equal(g, 0), axis=-1, keepdims=True)
for g in sparse_grads
]
original_lr = self.optimizer.lr
for f, p in zip(sparse_flags, sparse_params):
self.optimizer.lr = original_lr * K.cast(f, 'float32')
# updates only when gradients are not equal to zeros.
# (gradients are equal to zeros means these words are not sampled very likely.)
# 仅更新梯度不为0的Embedding（梯度为0意味着这些词很可能是没被采样到的）
self.updates.extend(self.optimizer.get_updates(loss, [p]))
self.optimizer.lr = original_lr
return self.updates
def one_hot_it(label, label_values):
"""
Convert a segmentation image label array to one-hot format
by replacing each pixel value with a vector of length num_classes
# Arguments
label: The 2D array segmentation image label
label_values
# Returns
A 2D array with the same width and height as the input, but
with a depth size of num_classes
"""
semantic_map = []
for colour in label_values:
# colour_map = np.full((label.shape[0], label.shape[1], label.shape[2]), colour, dtype=int)
equality = K.equal(label, colour)
class_map = K.all(equality, axis = -1)
semantic_map.append(class_map)
semantic_map = K.stack(semantic_map, axis=-1)
return semantic_map