Retries in dask.compute() are unclear - dask

From the documentation, Number of allowed automatic retries if computing a result fails.
Does "result" refer to each individual task or the entire compute() call?
If it refers to the entire call, how to implement retries for each task in dask.delayed?
Also, I'm not sure if the retries are working at all, as per below code.
import dask
import random
#dask.delayed
def add(x, y):
return x + y
#dask.delayed
def divide(sum_i):
n = random.randint(0, 1)
result = sum_i / n
return result
tasks = []
for i in range(3):
sum_i = add(i, i+1)
divide_n = divide(sum_i)
tasks.append(divide_n)
dask.compute(*tasks, retries=1000)
Expected output is (1, 3, 5), actual is ZeroDivisionError.

If anyone is interested, we use a #retry decorator for tasks, like so:
#dask.delayed
#retry(Exception, tries=3, delay=5)
def my_func():
pass
Retry decorator:
from functools import wraps
def retry(exceptions, tries=4, delay=3, backoff=2, logger=None):
"""
Retry calling the decorated function using an exponential backoff.
Args:
exceptions: The exception to check. may be a tuple of
exceptions to check.
tries: Number of times to try (not retry) before giving up.
delay: Initial delay between retries in seconds.
backoff: Backoff multiplier (e.g. value of 2 will double the delay
each retry).
logger: Logger to use.
"""
if not logger:
logger = logging.getLogger(__name__)
def deco_retry(f):
#wraps(f)
def f_retry(*args, **kwargs):
mtries, mdelay = tries, delay
while mtries > 1:
try:
return f(*args, **kwargs)
except exceptions as e:
msg = f"{e}, \nRetrying in {mdelay} seconds..."
logger.warning(msg)
sleep(mdelay)
mtries -= 1
mdelay *= backoff
return f(*args, **kwargs)
return f_retry # true decorator
return deco_retry

Related

How to gather all client weights at server in TFF?

I am trying to implement a custom aggregation using TFF by changing the code from this tutorial . I would like to rewrite next_fn so that all the client weights are placed at the server for further computations. As federated_collect was removed from tff-nightly, I am trying to do that using federated_aggregate.
This is what I have so far:
def accumulate(x, y):
x.append(y)
return x
def merge(x, y):
x.extend(y)
return y
#tff.federated_computation(federated_server_type, federated_dataset_type)
def next_fn(server_state, federated_dataset):
server_weights_at_client = tff.federated_broadcast(
server_state.trainable_weights)
client_deltas = tff.federated_map(
client_update_fn, (federated_dataset, server_weights_at_client))
z = []
agg_result = tff.federated_aggregate(client_deltas, z,
accumulate=tff.tf_computation(accumulate),
merge=tff.tf_computation(merge),
report=tff.tf_computation(lambda x: x))
new_weights = do_smth_with_result(agg_result)
server_state = tff.federated_map(
server_update_fn, (server_state, new_weights))
return server_state
However this results in the following Exception:
File "/home/yana/Documents/Uni/Thesis/grufedatt_try.py", line 351, in <module>
def next_fn(server_state, federated_dataset):
File "/home/yana/anaconda3/envs/fedenv/lib/python3.9/site-packages/tensorflow_federated/python/core/impl/wrappers/computation_wrapper.py", line 494, in __call__
wrapped_func = self._strategy(
File "/home/yana/anaconda3/envs/fedenv/lib/python3.9/site-packages/tensorflow_federated/python/core/impl/wrappers/computation_wrapper.py", line 222, in __call__
result = fn_to_wrap(*args, **kwargs)
File "/home/yana/Documents/Uni/Thesis/grufedatt_try.py", line 358, in next_fn
agg_result = tff.federated_aggregate(client_deltas, z,
File "/home/yana/anaconda3/envs/fedenv/lib/python3.9/site-packages/tensorflow_federated/python/core/impl/federated_context/intrinsics.py", line 140, in federated_aggregate
raise TypeError(
TypeError: Expected parameter `accumulate` to be of type (<<<float32[9999,96],float32[96,1024],float32[256,1024],float32[1024],float32[256,96],float32[96]>>,<float32[9999,96],float32[96,1024],float32[256,1024],float32[1024],float32[256,96],float32[96]>> -> <<float32[9999,96],float32[96,1024],float32[256,1024],float32[1024],float32[256,96],float32[96]>>), but received (<<>,<float32[9999,96],float32[96,1024],float32[256,1024],float32[1024],float32[256,96],float32[96]>> -> <<float32[9999,96],float32[96,1024],float32[256,1024],float32[1024],float32[256,96],float32[96]>>) instead.
Try using tff.aggregators.federated_sample with max_num_samples being equal to the number of clients you have.
That should be a simple drop-in replacement for how you would previously use tff.federated_collect.
In your accumulate, the issue is that you are changing number of tensors the accumulator would contain, so you get an error when accumulating more than a single accumuland. If you would want to go this way though, for a rank-1 accumuland with k elements, you could probably do something like the following instead:
#tff.tf_computation(tff.types.TensorType(tf.float32, [None, k]),
tff.types.TensorType(tf.float32, [k]))
def accumulate(accumulator, accumuland):
return tf.concat([accumulator, tf.expand_dims(accumuland, axis=0)], axis=0)

Pipeline deployment in Flask (python)

I'm trying to deploy my model built using Pipeline via Flask, however I'm facing the following Attribute error
'Can't get attribute 'FeatureSelector' on main' from 'app.py''
Here is my code for model.py:
(After loading the necessary libraries and reading the data, I have defined the class for my pipeline)
class FeatureSelector( BaseEstimator, TransformerMixin ):
#Class Constructor
def __init__( self, feature_names ):
self._feature_names = feature_names
#Return self nothing else to do here
def fit( self, X, y =None):
return self
#Method that describes what we need this transformer to do
def transform( self, X, y = None):
return X[ self._feature_names ]
LE = LabelEncoder()
class CategoricalTransformer( BaseEstimator, TransformerMixin ):
#Class constructor method that takes in a list of values as its argument
def __init__(self, cat_cols = ['Response', 'EmploymentStatus', 'Number of Open Complaints',
'Number of Policies', 'Policy Type', 'Renew Offer Type',
'Vehicle Class']):
self._cat_cols = cat_cols
#Return self nothing else to do here
def fit( self, X, y = None ):
return self
#Transformer method we wrote for this transformer
def transform(self, X , y = None ):
if self._cat_cols:
for i in X[cat_cols]:
X[i]= LE.fit_transform(X[i])
return X.values
class NumericalTransformer(BaseEstimator, TransformerMixin):
#Class Constructor
def __init__( self, MPA_log = True):
self._MPA_log = MPA_log
#Return self, nothing else to do here
def fit( self, X, y = None):
return self
#Custom transform method we wrote that creates aformentioned features and drops redundant ones
def transform(self, X, y = None):
if self._MPA_log:
X.loc[:,'MPA_log'] = np.log(X['Monthly Premium Auto'])
X.drop(['Monthly Premium Auto'], axis =1)
return X.values
I have created different pipelines for numerical and categorical festures. They have been combined using Feture Union in Full Pipeline.
full_pipeline = FeatureUnion( transformer_list = [ ( 'categorical_pipeline', categorical_pipeline ), ( 'numerical_pipeline', numerical_pipeline ) ] )
X = df.drop('Customer Lifetime Value', axis = 1)
y = df['Customer Lifetime Value']
y = np.log(y) #Transforming the y variable
full_pipeline_RF = Pipeline( steps = [('full_pipeline', full_pipeline),('model',
RandomForestRegressor(max_depth=21, min_samples_leaf= 8, random_state=0))])
full_pipeline_RF.fit(X, y)
# Saving model to disk
pickle.dump(full_pipeline_RF, open('model.pkl','wb'))
# Loading model to compare the results
model = pickle.load(open('model.pkl','rb'))
Model has been called in app.py file with the following code:
import numpy as np
from flask import Flask, request, jsonify, render_template
import pickle
app = Flask(__name__)
model = pickle.load(open('model.pkl', 'rb'))
#app.route('/')
def home():
return render_template('index.html')
#app.route('/predict',methods=['POST'])
def predict():
'''
For rendering results on HTML GUI
'''
int_features = [float(x) for x in request.form.values()]
final_features = [np.array(int_features)]
prediction = model.predict(final_features)
output = round(np.exp(prediction[0]),2)
return render_template('index.html', prediction_text='Customer Lifetime Value $ {}'.format(output))
if __name__ == "__main__":
app.run(debug=True)
The code works fine in Jupyter. Even while running in Spyder, it doesnt throw any errors. Please help me with this code, I'm stuck only on the execution bit.
This was actually simple. All i had to do was jn my app.py I had to pass the classes created during pipeline.
These are new classes customised for the case, hence those classes need to be pass.
Simply write 'pass' after every class is defined.

OpenAI gym breakout-ram-v4 unable to learn

I am using Q learning and the program should be able to play the game after some tries but it is not learning even when the epsilon value if 0.1.
I have tried changing the batch size the memory size. I have changed the code to give -1 reward if the player dies.
import gym
import numpy as np
import random
import tensorflow as tf
import numpy as np
from time import time
import keyboard
import sys
import time
env = gym.make("Breakout-ram-v4")
observationSpace = env.observation_space
actionSpace= env.action_space
episode = 500
class Model_QNN :
def __init__(self):
self.memory = []
self.MAX_MEMORY_TO_USE = 60_000
self.gamma = 0.9
self.model = tf.keras.Sequential([
tf.keras.layers.Flatten(input_shape=(128,1)),
tf.keras.layers.Dense(256,activation="relu"),
tf.keras.layers.Dense(64,activation="relu"),
tf.keras.layers.Dense(actionSpace.n , activation= "softmax")
])
self.model.compile(optimizer="adam",loss="mse",metrics=["accuracy"])
def remember(self, steps , done):
self.memory.append([steps,done])
if(len(self.memory) >= self.MAX_MEMORY_TO_USE):
del self.memory[0]
def replay(self,batch_size= 32):
states, targets_f = [], []
if(len(self.memory)< batch_size) :
return
else:
mini = random.sample(self.memory,batch_size)
states ,targets = [], []
for steps , done in mini :
target= steps[2] ;
if not done :
target = steps[2] + (self.gamma* np.amax(self.model.predict(steps[3].reshape(1,128,1))[0]))
target_f = self.model.predict(steps[0].reshape(1,128,1))
target_f[0][steps[1]] = target
states.append(steps[0])
targets.append(target_f[0])
self.model.fit(np.array(states).reshape(len(states),128,1), np.array(targets),verbose=0,epochs=10)
def act(self,state,ep):
if(random.random()< ep):
action = actionSpace.sample()
else :
np.array([state]).shape
action= self.model.predict(state.reshape(1,128,1))
action = np.argmax(action)
return action;
def saveModel (self):
print("Saving")
self.model.save("NEWNAMEDONE")
def saveBackup(self,num):
self.model.save("NEWNAME"+str(int(num)))
def main():
agent= Model_QNN();
epsilon=0.9
t_end = time.time()
score= 0
for e in range(2000):
print("Working on episode : "+str(e)+" eps "+str(epsilon)+" Score " + str(score))
preState = env.reset()
preState,reward,done,_ = env.step(1)
mainLife=5
done = False
score= 0
icount = 0
render=False
if e % 400 ==0 and not e==0:
render =True
while not done:
icount+=1
if render:
env.render()
if keyboard.is_pressed('q'):
agent.saveBackup(100)
agent.saveModel()
quit()
rewrd=0
if ( _["ale.lives"] < mainLife ):
mainLife-=1
rewrd=-1
action=1
else:
action = agent.act(preState,epsilon)
newState,reward,done,_ = env.step(action)
if rewrd ==-1 :
reward =-1
agent.remember([preState/255,action,reward,newState/255],done);
preState= newState;
score+=reward
if done :
break
agent.replay(1024)
if epsilon >= 0.18 :
epsilon = epsilon * 0.995;
if ((e+1)%500==0):
agent.saveBackup((e+1)/20)
agent.saveModel()
if __name__=='__main__':
main()
There is no error message the program should learn and it is not
Why are you using Softmax on your output layer?
If you want to use Softmax use Cross-Entropy as your loss. However, it looks like you're trying to implement a value based learning system. The activation function on your output layer should be linear.
I suggest you try your implementation on Cartpole-v0 then LunarLanding-v2 first.
Those are solved environments and a great place to sanity check your code.
"There is no error message the program should learn and it is not."
Welcome to ML where things fail silently.

Unable to get pipeline.fit() to work using Sklearn and Keras Wrappers

I am getting a value error for parameters (not enough to unpack expected 2 got 1) I have a network I want to train:
def build(self):
numpy.random.seed(self.seed)
self.estimators.append(('standardize', StandardScaler))
self.estimators.append(('mlp', KerasClassifier(build_fn=self.build_fn, epochs=50, batch_size=5, verbose=0)))
self.pipeline = Pipeline(self.estimators)
Now if I want to fit the data to some values: say self.X, self.Y
self.model = self.pipeline.fit(self.X, self.Y, verbose=1)
I get
Traceback (most recent call last):
File "C:/Users/jaehan/PycharmProjects/cerebro/cerebro.py", line 257, in
<module>
model.run()
File "C:/Users/jaehan/PycharmProjects/cerebro/cerebro.py", line 138, in run
self.model = self.pipeline.fit(self.X, self.Y, verbose=1)
File "C:\Users\jaehan\AppData\Local\Continuum\anaconda3\envs\py36\lib\site-
packages\sklearn\pipeline.py", line 248, in fit
Xt, fit_params = self._fit(X, y, **fit_params)
File "C:\Users\jaehan\AppData\Local\Continuum\anaconda3\envs\py36\lib\site-
packages\sklearn\pipeline.py", line 197, in _fit
step, param = pname.split('__', 1)
ValueError: not enough values to unpack (expected 2, got 1)
Am I doing something wrong here? I was under the impression I could just run a fit and it would return a history object, which I could save and load at any time
I even tried...
self.pipeline.fit(self.X, self.Y)
Which throws...
AttributeError: 'numpy.ndarray' object has no attribute 'fit'
I have no idea what is going on here.
Full Code
class Cerebro:
def __init__(self):
self.model = None
self.build_fn = None
self.data = None
self.X = None
self.Y = None
#these three are for encoding string values to integer_encodings / one hot encodings
self.encoder = LabelEncoder()
self.encodings = {}
self.one_hot_encodings = {}
self.seed = numpy.random.seed(7) #this is to ensure we have reproducible results.
self.estimators = []
self.pipeline = None
self.kfold = StratifiedKFold(n_splits=10, shuffle=True, random_state=self.seed)
self.cross_validation_score = 0.0
def preprocess(self):
"""
This method will preprocess the dataset we want to train our network on.
Example:
import preproccessing
...
dataset, X, Y = preprocessing.main()
"""
self.data = pandas.read_csv('src_examples/hwtxn_final_for_influx.txt', sep='\t').values
self.X = numpy.delete(self.data, 13, axis=1)
self.Y = self.data[:, 13].astype(numpy.float16)
def build(self):
self.build_fn = self.base_model()
self.preprocess()
numpy.random.seed(self.seed)
self.estimators.append(('standardize', StandardScaler()))
self.estimators.append(('mlp', KerasClassifier(build_fn=self.build_fn, epochs=50, batch_size=5, verbose=0)))
self.pipeline = Pipeline(self.estimators)
def run(self):
"""This will actually take the pipeline (preprocessing standardization, model)
and fit it to our dataset (X, Y) (We don't need test/train since we are using stratified k fold cross val.)
Args:
None
Returns:
None
"""
# this is the 'model'
# self.pipeline
print(type(self.pipeline))
print(self.X.shape)
self.model = self.pipeline.fit(self.X, self.Y)
def load(self, fn):
"""This will load a saved model (history object)
Args:
fn (filename): represents saved model file
Returns:
model (pkl object): represents model
"""
return pickle.load(open(fn, 'rb'))
def save(self, fn):
"""This will save a model (history object)
Args:
fn (filename): represents a filename to save the model as
Returns:
None
"""
pickle.dump(self.model, open(fn, 'wb'))
def encode(self, vals, key):
""" This method will encode a list of values and take a key (representing column name, or index) to save
in the class object (self.encodings)
This will help us keep track of encodings we have for values we need to translate/decipher.
Args:
vals(np.array): array of values to encode
key(str): str representing the key used to encode this particular set of values
Returns:
transformed values (np.array) representing the encoded versions of values
"""
# int encoding for non int values
self.encodings[key] = self.encoder.fit_transform(vals)
return self.encoder.fit_transform(vals)
def decoder(self, vals, key):
"""This method will decode the integer_encodings for class variables. It will take vals which
represents a list of values to decode (i.e. [1,2,3] -- [apple, pear, orange])
It will also take a key (since every decoding has a corresponding encoding) to find which encoding
scheme to map to
Args:
vals(np.array) : array of values to decode
key(str) : string representing the key used for encoding the values (for decoding it)
Returns:
inverse transform of encoded values (np.array)
"""
# translate int encodings to original values (encoder._classes)
return self.encodings[key].inverse_transform(vals)
def cross_validate(self):
"""
This will perform a cross validation score using a stratified kfold method. (Think traditional Kfold but
with the values evenly distributed for each subsample)
Args:
None
Returns:
None
"""
self.cross_validation_score = cross_val_score(self.pipeline, self.X, self.Y, cv=self.kfold)
return self.cross_validation_score
#staticmethod
def base_model():
"""
This will return a base model for us to try. The good thing about this implementation is that
when we decide we want something more complex then all we have to do is define a class function and replace
the values in the build f(x)
Args:
None
Returns:
model (keras.models.Sequential): Keras based DNN Model
"""
# create model
model = Sequential()
model.add(Dense(60, input_dim=60, kernel_initializer='normal', activation='relu'))
model.add(Dense(1, kernel_initializer='normal', activation='sigmoid'))
# Compile model
model.compile(loss='binary_crossentropy', optimizer='adam', metrics=['accuracy'])
return model
#staticmethod
def one_hot_encoder(int_encoding):
"""
This will take an integer encoding of string variables (traditional preprocessing step, will probably
move this to the preprocessing package.
Essential it returns a binary 'one hot' encoding of the values we wish to encode
Example
#Dataset Values
[apple, orange, pear]
#Integer Encoding
[1, 2, 3]
#One Hot Encoding
[[1, 0, 0]
[0, 1, 0]
[0, 0, 1]]
Args:
None
Returns:
Matrix (np.array): matrix representing one hot vectors for a class of values
"""
# we might not need this... so for now we will keep it static
return OneHotEncoder(sparse=False).fit_transform(int_encoding.reshape(len(int_encoding), 1))
if __name__ == '__main__':
# Step 1 is to initialize class (with seed == 7)
model = Cerebro()
model.build()
model.cross_validate()
print("Here are our estimators:\n {}".format(model.estimators))
print("Here is our pipeline:\n {}".format(model.pipeline))
model.run()
EDIT
The answer is that .fit() build_fn argument requires a function pointer and not the model itself.
IMHO I feel an error should be thrown for specifically that case.
This is due to the following line:
self.build_fn = self.base_model()
This should actually be:
self.build_fn = self.base_model
KerasClassifier requires a pointer to the function which creates the model, but by appending () at the end, you are assigning build_fn with the actual model, which is wrong.
Now in addition to above error, I would recommend checking the following lines in your code, which if not corrected will give error in future when you will use the code.
1) self.encodings[key] = self.encoder.fit_transform(vals)
Here you are assigning the transformed data to the encodings[key] not the model. So when you do this:-
self.encodings[key].inverse_transform(vals)
It makes no sense to call inverse_transform() on the transformed data.
inverse_transform() is a method of scikit-learn transformers. But self.encodings[key] will give out a ndarray, because you have saved the output array from fit_transform().
2) Something similar to 2 is also happening with one_hot_encoder()
The error "AttributeError: 'numpy.ndarray' object has no attribute 'fit'" seems related to 1 and 2.

Can someone explain the train function in cifar10_train.py from cifar10 tutorials in tensorflow

I am following cifar10 tutorials from https://github.com/tensorflow/models/tree/master/tutorials/image/cifar10.
In this project, there are 6 classes. After searching the internet I understood cifar10.py and cifar10_input.py classes. But I can't understand train function in cifar10_train.py. Here is the train function in cifar10_train.py class.
def train():
with tf.Graph().as_default():
global_step = tf.contrib.framework.get_or_create_global_step()
# get images and labels for cifar 10
# Force input pipeline to CPU:0 to avoid operations sometime ending on
# GPU and resulting in a slow down
with tf.device('/cpu:0'):
images, labels = cifar10.distorted_inputs()
logits = cifar10.inference(images)
loss = cifar10.loss(logits, labels)
train_op = cifar10.train(loss, global_step)
class _LoggerHook(tf.train.SessionRunHook):
def begin(self):
self._step = -1
self._start_time = time.time()
def before_run(self, run_context):
self._step += 1
return tf.train.SessionRunArgs(loss)
def after_run(self, run_context, run_values):
if self._step % FLAGS.log_frequency == 0:
current_time = time.time()
duration = current_time - self._start_time
self._start_time = current_time
loss_value = run_values.results
examples_per_sec = FLAGS.log_frequency * FLAGS.batch_size / duration
sec_per_batch = float(duration / FLAGS.log_frequency)
format_str = ('%s: step %d, loss = %.2f (%.1f examples/sec; %.3f '
'sec/batch)')
print(format_str % (datetime.now(), self._step, loss_value,
examples_per_sec, sec_per_batch))
with tf.train.MonitoredTrainingSession(
checkpoint_dir=FLAGS.train_dir,
hooks=[tf.train.StopAtStepHook(last_step=FLAGS.max_steps),
tf.train.NanTensorHook(loss),
_LoggerHook()],
config=tf.ConfigProto(
log_device_placement=FLAGS.log_device_placement)) as mon_sess:
while not mon_sess.should_stop():
mon_sess.run(train_op)
Can someone please explain what is happening in _LoggerHook class?
It uses MonitoredSession and SessionRunHook for logging the loss when training.
_LoggerHook is an implementation of SessionRunHook that runs in an order described below:
call hooks.begin()
sess = tf.Session()
call hooks.after_create_session()
while not stop is requested:
call hooks.before_run()
try:
results = sess.run(merged_fetches, feed_dict=merged_feeds)
except (errors.OutOfRangeError, StopIteration):
break
call hooks.after_run()
call hooks.end()
sess.close()
It's from here.
It collects loss data before the session.run then outputs loss with a predefined format.
A tutorial: https://www.tensorflow.org/tutorials/layers
Hope this hopes.

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