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TfLearn Confusion Matrix training terminated on std::bad_alloc


Having problems working out how to get a confusion matrix when using TFLearn for the creation of a convolutional neural network. The code I have so far is as follows:

 from __future__ import division, print_function, absolute_import

    import tflearn
    from tflearn.layers.core import input_data, dropout, fully_connected
    from tflearn.layers.conv import conv_2d, max_pool_2d
    from tflearn.layers.normalization import local_response_normalization
    from tflearn.layers.estimator import regression

    from sklearn.metrics import confusion_matrix
    import h5py

    hdf5Test = h5py.File('/path', 'r')

    X = hdf5Test['X']
    Y = hdf5Test['Y']

    # Building convolutional network
    network = input_data(shape=[None, 240, 320, 3], name='input')
    network = conv_2d(network, 32, 3, activation='relu', regularizer="L2")
    network = max_pool_2d(network, 2)
    network = local_response_normalization(network)
    network = conv_2d(network, 64, 3, activation='relu', regularizer="L2")
    network = max_pool_2d(network, 2)
    network = local_response_normalization(network)
    network = fully_connected(network, 128, activation='tanh')
    network = dropout(network, 0.8)
    network = fully_connected(network, 256, activation='tanh')
    network = dropout(network, 0.8)
    network = fully_connected(network, 2, activation='softmax')
    network = regression(
      network,
      optimizer='sgd',
      learning_rate=0.01,
      loss='categorical_crossentropy',
      name='target'
    )

    # Training
    model = tflearn.DNN(network, tensorboard_verbose=0)
    model.load('/path.tflearn')

    predictions = model.predict(X)
    print(confusion_matrix(Y, predictions))

Everytime I try to run this code I am given the following error message:

terminate called after throwing an instance of 'std::bad_alloc' what(): std::bad_alloc Aborted (core dumped)

Any advice would be great, new to TFLearn.


Solution

  • In the end, it found that it was due to the size of the data I was trying to predict. I fixed this by inserting it within a loop:

    # Predict Classes
    predictions = []
    count = 0
    length = len(X)
    for line in X:
      print('Line ' + str(count) + ' of ' + str(length))
      tmp = model.predict_label([line])
      predictions.append(tmp[0])
      count += 1
    

    With some formatting I was then able to use Sklearn to produce a confusion matrix:

    predictedClasses = np.argmin(predictions, axis=1)
    actualClasses = np.argmax(Y, axis=1)
    print(confusion_matrix(actualClasses, predictedClasses))
    

    This approach worked for me and may work for you... I think TFLearn should look into a streamlined approach for the production of confusion matrix so other don't have the same problem.