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How to save final model using keras?

I use KerasClassifier to train the classifier.

The code is below:

import numpy
from pandas import read_csv
from keras.models import Sequential
from keras.layers import Dense
from keras.wrappers.scikit_learn import KerasClassifier
from keras.utils import np_utils
from sklearn.model_selection import cross_val_score
from sklearn.model_selection import KFold
from sklearn.preprocessing import LabelEncoder
from sklearn.pipeline import Pipeline
# fix random seed for reproducibility
seed = 7
numpy.random.seed(seed)
# load dataset
dataframe = read_csv("iris.csv", header=None)
dataset = dataframe.values
X = dataset[:,0:4].astype(float)
Y = dataset[:,4]
# encode class values as integers
encoder = LabelEncoder()
encoder.fit(Y)
encoded_Y = encoder.transform(Y)
#print("encoded_Y")
#print(encoded_Y)
# convert integers to dummy variables (i.e. one hot encoded)
dummy_y = np_utils.to_categorical(encoded_Y)
#print("dummy_y")
#print(dummy_y)
# define baseline model
def baseline_model():
    # create model
    model = Sequential()
    model.add(Dense(4, input_dim=4, init='normal', activation='relu'))
    #model.add(Dense(4, init='normal', activation='relu'))
    model.add(Dense(3, init='normal', activation='softmax'))
    # Compile model
    model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])

    return model

estimator = KerasClassifier(build_fn=baseline_model, nb_epoch=200, batch_size=5, verbose=0)
#global_model = baseline_model()
kfold = KFold(n_splits=10, shuffle=True, random_state=seed)
results = cross_val_score(estimator, X, dummy_y, cv=kfold)
print("Accuracy: %.2f%% (%.2f%%)" % (results.mean()*100, results.std()*100))

But How to save the final model for future prediction?

I usually use below code to save model:

# serialize model to JSON
model_json = model.to_json()
with open("model.json", "w") as json_file:
    json_file.write(model_json)
# serialize weights to HDF5
model.save_weights("model.h5")
print("Saved model to disk")

But I don't know how to insert the saving model's code into KerasClassifier's code.

Thank you.


b
bogatron

The model has a save method, which saves all the details necessary to reconstitute the model. An example from the keras documentation:

from keras.models import load_model

model.save('my_model.h5')  # creates a HDF5 file 'my_model.h5'
del model  # deletes the existing model

# returns a compiled model
# identical to the previous one
model = load_model('my_model.h5')

sorry, I mean cross_val_score's final weight.
Have you tried setting the callbacks keyword of your KerasClassifier equal to a list whose single item is an instance of a keras ModelCheckpoint?
No, I don't know ModelCheckpoint. Could you explain more detail about it.Thanks
Follow the link in my comment for details. The ModelCheckpoint callback is used to save the model after each training epoch (optionally only if the validation error decreases). It can save multiple files or a single (overwritten) file.
Executed above line of codes but at the time of load_model() its showing this error: ValueError: Cannot create group in read only mode.
M
MMK

you can save the model in json and weights in a hdf5 file format.

# keras library import  for Saving and loading model and weights

from keras.models import model_from_json
from keras.models import load_model

# serialize model to JSON
#  the keras model which is trained is defined as 'model' in this example
model_json = model.to_json()


with open("model_num.json", "w") as json_file:
    json_file.write(model_json)

# serialize weights to HDF5
model.save_weights("model_num.h5")

files "model_num.h5" and "model_num.json" are created which contain our model and weights

To use the same trained model for further testing you can simply load the hdf5 file and use it for the prediction of different data. here's how to load the model from saved files.

# load json and create model
json_file = open('model_num.json', 'r')

loaded_model_json = json_file.read()
json_file.close()
loaded_model = model_from_json(loaded_model_json)

# load weights into new model
loaded_model.load_weights("model_num.h5")
print("Loaded model from disk")

loaded_model.save('model_num.hdf5')
loaded_model=load_model('model_num.hdf5')

To predict for different data you can use this

loaded_model.predict_classes("your_test_data here")

I tried to use your code it saved the model but at the time of loading it's giving this error: ValueError: Unknown initializer: GlorotUniform. Can you please suggest how to solve this?
Thanks for reply MMK. But I found the solution I have explained it below in the answer.
p
prosti

You can use model.save(filepath) to save a Keras model into a single HDF5 file which will contain:

the architecture of the model, allowing to re-create the model.

the weights of the model.

the training configuration (loss, optimizer)

the state of the optimizer, allowing to resume training exactly where you left off.

In your Python code probable the last line should be:

model.save("m.hdf5")

This allows you to save the entirety of the state of a model in a single file. Saved models can be reinstantiated via keras.models.load_model().

The model returned by load_model() is a compiled model ready to be used (unless the saved model was never compiled in the first place).

model.save() arguments:

filepath: String, path to the file to save the weights to.

overwrite: Whether to silently overwrite any existing file at the target location, or provide the user with a manual prompt.

include_optimizer: If True, save optimizer's state together.


There is some ambiguity within this answer, because now there exist two save formats. The older one is the Keras H5 format. This can format can be chosen, by entering a file name with extension .h5, .hdf5 or .keras or by passing save_format='h5' to save(). The newer format is the TensorFlow SavedModel format, which consist of several files and folders within a folder. This will be taken, if the "filepath" does not end with a file with one of the three above given extensions. (See keras documentation at tensorflow.org.)
m
markemus

you can save the model and load in this way.

from keras.models import Sequential, load_model
from keras_contrib.losses import import crf_loss
from keras_contrib.metrics import crf_viterbi_accuracy

# To save model
model.save('my_model_01.hdf5')

# To load the model
custom_objects={'CRF': CRF,'crf_loss':crf_loss,'crf_viterbi_accuracy':crf_viterbi_accuracy}

# To load a persisted model that uses the CRF layer 
model1 = load_model("/home/abc/my_model_01.hdf5", custom_objects = custom_objects)

N
NelsonGon

Generally, we save the model and weights in the same file by calling the save() function.

For saving,

model.compile(optimizer='adam',
              loss = 'categorical_crossentropy',
              metrics = ["accuracy"])

model.fit(X_train, Y_train,
         batch_size = 32,
         epochs= 10,
         verbose = 2, 
         validation_data=(X_test, Y_test))

#here I have use filename as "my_model", you can choose whatever you want to.

model.save("my_model.h5") #using h5 extension
print("model saved!!!")

For Loading the model,

from keras.models import load_model

model = load_model('my_model.h5')
model.summary()

In this case, we can simply save and load the model without re-compiling our model again. Note - This is the preferred way for saving and loading your Keras model.


This is in principle the same answer as the oldest answer posted by bogatron on Mar 13 '17 at 12:10.
C
Charith Jayasanka

Saving a Keras model:

model = ...  # Get model (Sequential, Functional Model, or Model subclass)
model.save('path/to/location')

Loading the model back:

from tensorflow import keras
model = keras.models.load_model('path/to/location')

For more information, read Documentation


R
Ransaka Ravihara

You can save the best model using keras.callbacks.ModelCheckpoint()

Example:

model.compile(loss='categorical_crossentropy', optimizer='adam', metrics=['accuracy'])
model_checkpoint_callback = keras.callbacks.ModelCheckpoint("best_Model.h5",save_best_only=True)
history = model.fit(x_train,y_train,
          epochs=10,
          validation_data=(x_valid,y_valid),
          callbacks=[model_checkpoint_callback])

This will save the best model in your working directory.


f
feli_x

Since the syntax of keras, how to save a model, changed over the years I will post a fresh answer. In principle the earliest answer of bogatron, posted Mar 13 '17 at 12:10 is still good, if you want to save your model including the weights into one file.

model.save("my_model.h5")

This will save the model in the older Keras H5 format.

However, there is a new format, the TensorFlow SavedModel format, which will be used if you do not specify the extension .h5, .hdf5 or .keras after the filename.

The syntax in this case is

model.save("path/to/folder")

If the given folder name does not yet exist, it will be created. Two files and two folders will be created within this folder:

keras_metadata.pb, saved_model.pb, assets, variables

So far you can still decide whether you want to store your model into one single file or into a folder containing files and folders. (See keras documentation at www.tensorflow.org.)