Referring to this Link, (the Link)
I try to practice using tf.contrib.factorization.KMeansClustering for clustering. The simple codes as follow works okay:
import numpy as np
import tensorflow as tf
# ---- Create Data Sample -----
k = 5
n = 100
variables = 5
points = np.random.uniform(0, 1000, [n, variables])
# ---- Clustering -----
input_fn=lambda: tf.train.limit_epochs(tf.convert_to_tensor(points, dtype=tf.float32), num_epochs=1)
kmeans=tf.contrib.factorization.KMeansClustering(num_clusters=6)
kmeans.train(input_fn=input_fn)
centers = kmeans.cluster_centers()
# ---- Print out -----
cluster_indices = list(kmeans.predict_cluster_index(input_fn))
for i, point in enumerate(points):
cluster_index = cluster_indices[i]
print ('point:', point, 'is in cluster', cluster_index, 'centered at', centers[cluster_index])
My question is why would this "input_fn" code does the trick?
If I change the code to this, it will run into an infinite loop. Why??
input_fn=lambda:tf.convert_to_tensor(points, dtype=tf.float32)
From the document (here), it seems that train() is expecting argument of input_fn, which is simply a A 'tf.data.Dataset' object , like Tensor(X). So, why do I have to do all these tricky things regarding lambda: tf.train.limit_epochs()?
Can anyone who is familiar with the fundamental of tensorflow estimators help to explain? Many Thanks!
My question is why would this "input_fn" code does the trick? If I change the code to this, it will run into an infinite loop. Why??
The documentation states that input_fn is called repeatedly until it returns a tf.errors.OutOfRangeError. Adorning your tensor with tf.train.limit_epochs ensures that the error is eventually raised, which signals to KMeans that it should stop training.
Related
I would like to convert the ActorDistributionModel from a trained PPOClipAgent into a Tensorflow Lite model for deployment. How should I accomplish this?
I have tried following this tutorial (see section at bottom converting policy to TFLite), but the network outputs a single action (the policy) rather than the density function over actions that I desire.
I think perhaps something like this could work:
tf.compat.v2.saved_model.save(actor_net, saved_model_path, signature=?)
... if I knew how to set the signature parameter. That line of code executes without error when I omit the signature parameter, but I get the following error on load (I assume because the signature is not set up correctly):
converter = tf.lite.TFLiteConverter.from_saved_model(saved_model_path)
File "/home/ais/salesmentor.ai/MDPSolver/src/solver/ppo_budget.py", line 336, in train_eval
converter = tf.lite.TFLiteConverter.from_saved_model(saved_model_path)
File "/home/ais/.local/lib/python3.9/site-packages/tensorflow/lite/python/lite.py", line 1275, in from_saved_model
raise ValueError("Only support a single signature key.")
ValueError: Only support a single signature key.
This appears to work. I won't accept the answer until I have completed an end-to-end test, though.
def export_model(actor_net, observation_spec, saved_model_path):
predict_signature = {
'action_pred':
tf.function(func=lambda x: actor_net(x, None, None)[0].logits,
input_signature=(tf.TensorSpec(shape=observation_spec.shape),)
)
}
tf.saved_model.save(actor_net, saved_model_path, signatures=predict_signature)
# Convert to TensorFlow Lite model.
converter = tf.lite.TFLiteConverter.from_saved_model(saved_model_path,
signature_keys=["action_pred"])
converter.target_spec.supported_ops = [
tf.lite.OpsSet.TFLITE_BUILTINS, # enable TensorFlow Lite ops.
tf.lite.OpsSet.SELECT_TF_OPS # enable TensorFlow ops.
]
tflite_policy = converter.convert()
with open(os.path.join(saved_model_path, 'policy.tflite'), 'wb') as f:
f.write(tflite_policy)
The solution wraps the actor_net in a lambda because I was unable to figure out how to specify the signature with all three expected arguments. Through the lambda, I convert the function into using a single argument (a tensor). I expect to pass None to the other two arguments in my use case, so there is nothing lost in this approach.
I see you using CartPole as the model simulation, Agent DQN, and Model learning and Evaluation from links provided TF-Agent Checkpointer. For simple understanding, you need to understand about the distributions and your model limits ( less than 6 actions determining at a time ).
Discretes Distribution, answer the question to the points but the links is how they implement AgentDQN on TF- Agent.
temp = tf.random.normal([10], 1, 0.2, tf.float32), mean is one and the standard deviation is 0.2. Overall of result summation product is nearby one and its variance is 0.2, when they have 10 actions to determine the possibility of the result is the same action is 1 from 5 or 0.5. random normal
Coefficient is ladder steps or you understand as IF and ELSE conditions or SWITCH conditions such as at the gap of 0 to 5, 5 to 10, 10 to 15, and continue.
The matrixes product from the Matrix coefficients and randoms is selected 4 - 5 actions sorted by priority, significant and select the most effects in rows.
The ArgMax is 0 to 9 which is actions 0 - 9 that respond to the environment input co-variances.
Sample: To the points, random distributions and selective agents ( we call selective agent maybe the questioner has confused with NN DQN )
temp = tf.random.normal([10], 1, 0.2, tf.float32)
temp = np.asarray(temp) * np.asarray([ coefficient_0, coefficient_1, coefficient_2, coefficient_3, coefficient_4, coefficient_5, coefficient_6, coefficient_7, coefficient_8, coefficient_9 ])
temp = tf.nn.softmax(temp)
action = int(np.argmax(temp))
I used the tensorflow tf.keras.metrics.MeanSquaredError() metric to evaluate the mean squared error between two numpy arrays. But each time I call mse() it give a different result.
a = np.random.random(size=(100,2000))
b = np.random.random(size=(100,2000))
for i in range(100):
v = mse(a, b).numpy()
plt.scatter(i,v)
print(v)
where I had previously defined mse = tf.keras.metrics.MeanSquaredError() Here is the Output. Any idea what is going wrong?
np.random.random generates random data every run. So, your code should result in different mse, shouldn't it?
run 1:
[0.87148841 0.50221413 0.49858526 ... 0.22311888 0.71320089 0.36298912]
Run 2:
[0.14941241 0.78560523 0.62436783 ... 0.1865485 0.2730567 0.49300401]
I'm in the process of completing a TensorFlow tutorial via DataCamp and am transcribing/replicating the code examples I am working through in my own Jupyter notebook.
Here are the original instructions from the coding problem :
I'm running the following snippet of code and am not able to arrive at the same result that I am generating within the tutorial, which I have confirmed are the correct values via a connected scatterplot of x vs. loss_function(x) as seen a bit further below.
# imports
import tensorflow as tf
import numpy as np
import matplotlib.pyplot as plt
from tensorflow import Variable, keras
def loss_function(x):
import math
return 4.0*math.cos(x-1)+np.divide(math.cos(2.0*math.pi*x),x)
# Initialize x_1 and x_2
x_1 = Variable(6.0, np.float32)
x_2 = Variable(0.3, np.float32)
# Define the optimization operation
opt = keras.optimizers.SGD(learning_rate=0.01)
for j in range(100):
# Perform minimization using the loss function and x_1
opt.minimize(lambda: loss_function(x_1), var_list=[x_1])
# Perform minimization using the loss function and x_2
opt.minimize(lambda: loss_function(x_2), var_list=[x_2])
# Print x_1 and x_2 as numpy arrays
print(x_1.numpy(), x_2.numpy())
I draw a quick connected scatterplot to confirm (successfully) that the loss function that I using gets me back to the same graph provided by the example (seen in screenshot above)
# Generate loss_function(x) values for given range of x-values
losses = []
for p in np.linspace(0.1, 6.0, 60):
losses.append(loss_function(p))
# Define x,y coordinates
x_coordinates = list(np.linspace(0.1, 6.0, 60))
y_coordinates = losses
# Plot
plt.scatter(x_coordinates, y_coordinates)
plt.plot(x_coordinates, y_coordinates)
plt.title('Plot of Input values (x) vs. Losses')
plt.xlabel('x')
plt.ylabel('loss_function(x)')
plt.show()
Here are the resulting global and local minima, respectively, as per the DataCamp environment :
4.38 is the correct global minimum, and 0.42 indeed corresponds to the first local minima on the graphs RHS (when starting from x_2 = 0.3)
And here are the results from my environment, both of which move opposite the direction that they should be moving towards when seeking to minimize the loss value:
I've spent the better part of the last 90 minutes trying to sort out why my results disagree with those of the DataCamp console / why the optimizer fails to minimize this loss for this simple toy example...?
I appreciate any suggestions that you might have after you've run the provided code in your own environments, many thanks in advance!!!
As it turned out, the difference in outputs arose from the default precision of tf.division() (vs np.division()) and tf.cos() (vs math.cos()) -- operations which were specified in (my transcribed, "custom") definition of the loss_function().
The loss_function() had been predefined in the body of the tutorial and when I "inspected" it using the inspect package ( using inspect.getsourcelines(loss_function) ) in order to redefine it in my own environment, the output of said inspection didn't clearly indicate that tf.division & tf.cos had been used instead of their NumPy counterparts (which my version of the code had used).
The actual difference is quite small, but is apparently sufficient to push the optimizer in the opposite direction (away from the two respective minima).
After swapping in tf.division() and tf.cos (as seen below) I was able to arrive at the same results as seen in the DC console.
Here is the code for the loss_function that will back in to the same results as seen in the console (screenshot) :
def loss_function(x):
import math
return 4.0*tf.cos(x-1)+tf.divide(tf.cos(2.0*math.pi*x),x)
Here is the code sample:
https://github.com/keiserlab/keras-neural-graph-fingerprint/blob/master/NGF/layers.py
in the beginning, it has
import theano.tensor as T
import keras.backend as K
However, I want to use tensorflow as backend. How can I modify the code?
Also, Later the programmer use some code like
# Set pad value and set subtensor of actual tensor
output = T.set_subtensor(output[:, :paddings[0], :], padvalue)
output = T.set_subtensor(output[:, paddings[1]:, :], padvalue)
output = T.set_subtensor(output[:, paddings[0]:x.shape[1] + paddings[0], :], x)
Do I need to also change this code since I change the backen?
Thanks
Trying debug statements in Python/tensorflow1.0 using jupyter , but does not get any output printed from tf.Print
Thought sess.run(during training in below code) should have evaluated db1 tensor and print output which did not happen
However db1.eval in evaluate phase , printing entire tensor X with out "message X:".
def combine_inputs(X):
db1=tf.Print(X,[X],message='X:')
return (tf.matmul(X, W) + b,db1)
<<training code>>
_,summary=sess.run([train_op,merged_summaries])
## merged_summaries tensor triggers combine_inputs function. There are
## other tensor functions/coding in between , not giving entire code to keep
## it simple; code works as expected except tf.Print
<<evaluate code>>
print(db1.eval())
Confused on following
a) Why tf.Print is not printing during sess.run during training?
b) Why explicit db1.eval is necessary , expected tf.Print to trigger with
sess.run. If eval is required , could copy tensor X in my code to db1
and evaluate it with out tf.Print. Correct?
Tried going through other questions (like below one). Suggested to implement memory_util or predefined function. As learner could not understand why tf.Print does not work in my scenario
If anyone encountered similar issues , please assist. Thanks!
Similar question in stackoverflow
According to the documentation, tf.Print prints to standard error (as of version 1.1), and it's not compatible with jupyter notebook. That's why you can't see any output.
Check here:
https://www.tensorflow.org/api_docs/python/tf/Print
You can check the terminal where you launched the jupyter notebook to see the message.
import tensorflow as tf
tf.InteractiveSession()
a = tf.constant(1)
b = tf.constant(2)
opt = a + b
opt = tf.Print(opt, [opt], message="1 + 2 = ")
opt.eval()
In the terminal, I can see:
2018-01-02 23:38:07.691808: I tensorflow/core/kernels/logging_ops.cc:79] 1 + 2 = [3]