dlnd_tv_script_generation


TV Script Generation

In this project, you'll generate your own Simpsons TV scripts using RNNs. You'll be using part of the Simpsons dataset of scripts from 27 seasons. The Neural Network you'll build will generate a new TV script for a scene at Moe's Tavern.

Get the Data

The data is already provided for you. You'll be using a subset of the original dataset. It consists of only the scenes in Moe's Tavern. This doesn't include other versions of the tavern, like "Moe's Cavern", "Flaming Moe's", "Uncle Moe's Family Feed-Bag", etc..


In [1]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
import helper

data_dir = './data/simpsons/moes_tavern_lines.txt'
text = helper.load_data(data_dir)
# Ignore notice, since we don't use it for analysing the data
text = text[81:]

Explore the Data

Play around with view_sentence_range to view different parts of the data.


In [2]:
view_sentence_range = (0, 10)

"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
import numpy as np

print('Dataset Stats')
print('Roughly the number of unique words: {}'.format(len({word: None for word in text.split()})))
scenes = text.split('\n\n')
print('Number of scenes: {}'.format(len(scenes)))
sentence_count_scene = [scene.count('\n') for scene in scenes]
print('Average number of sentences in each scene: {}'.format(np.average(sentence_count_scene)))

sentences = [sentence for scene in scenes for sentence in scene.split('\n')]
print('Number of lines: {}'.format(len(sentences)))
word_count_sentence = [len(sentence.split()) for sentence in sentences]
print('Average number of words in each line: {}'.format(np.average(word_count_sentence)))

print()
print('The sentences {} to {}:'.format(*view_sentence_range))
print('\n'.join(text.split('\n')[view_sentence_range[0]:view_sentence_range[1]]))


Dataset Stats
Roughly the number of unique words: 11492
Number of scenes: 262
Average number of sentences in each scene: 15.248091603053435
Number of lines: 4257
Average number of words in each line: 11.50434578341555

The sentences 0 to 10:
Moe_Szyslak: (INTO PHONE) Moe's Tavern. Where the elite meet to drink.
Bart_Simpson: Eh, yeah, hello, is Mike there? Last name, Rotch.
Moe_Szyslak: (INTO PHONE) Hold on, I'll check. (TO BARFLIES) Mike Rotch. Mike Rotch. Hey, has anybody seen Mike Rotch, lately?
Moe_Szyslak: (INTO PHONE) Listen you little puke. One of these days I'm gonna catch you, and I'm gonna carve my name on your back with an ice pick.
Moe_Szyslak: What's the matter Homer? You're not your normal effervescent self.
Homer_Simpson: I got my problems, Moe. Give me another one.
Moe_Szyslak: Homer, hey, you should not drink to forget your problems.
Barney_Gumble: Yeah, you should only drink to enhance your social skills.


Implement Preprocessing Functions

The first thing to do to any dataset is preprocessing. Implement the following preprocessing functions below:

  • Lookup Table
  • Tokenize Punctuation

Lookup Table

To create a word embedding, you first need to transform the words to ids. In this function, create two dictionaries:

  • Dictionary to go from the words to an id, we'll call vocab_to_int
  • Dictionary to go from the id to word, we'll call int_to_vocab

Return these dictionaries in the following tuple (vocab_to_int, int_to_vocab)


In [3]:
import numpy as np
import problem_unittests as tests

def create_lookup_tables(text):
    """
    Create lookup tables for vocabulary
    :param text: The text of tv scripts split into words
    :return: A tuple of dicts (vocab_to_int, int_to_vocab)
    """
    # TODO: Implement Function
    #print(text)
    
    vocab_to_int = {word: ii for ii, word in enumerate(set(text))}
    int_to_vocab = {ii: word for ii, word in enumerate(set(text))}

    
    return vocab_to_int, int_to_vocab


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_create_lookup_tables(create_lookup_tables)


Tests Passed

Tokenize Punctuation

We'll be splitting the script into a word array using spaces as delimiters. However, punctuations like periods and exclamation marks make it hard for the neural network to distinguish between the word "bye" and "bye!".

Implement the function token_lookup to return a dict that will be used to tokenize symbols like "!" into "||Exclamation_Mark||". Create a dictionary for the following symbols where the symbol is the key and value is the token:

  • Period ( . )
  • Comma ( , )
  • Quotation Mark ( " )
  • Semicolon ( ; )
  • Exclamation mark ( ! )
  • Question mark ( ? )
  • Left Parentheses ( ( )
  • Right Parentheses ( ) )
  • Dash ( -- )
  • Return ( \n )

This dictionary will be used to token the symbols and add the delimiter (space) around it. This separates the symbols as it's own word, making it easier for the neural network to predict on the next word. Make sure you don't use a token that could be confused as a word. Instead of using the token "dash", try using something like "||dash||".


In [4]:
def token_lookup():
    """
    Generate a dict to turn punctuation into a token.
    :return: Tokenize dictionary where the key is the punctuation and the value is the token
    """
    # TODO: Implement Function
    token_dd = {}
    token_dd['.']='||period||'
    token_dd[',']='||comma||'
    token_dd['"']='||quotation_mark||'
    token_dd[';']='||semicolon||'
    token_dd['!']='||exclamation_mark||'
    token_dd['?']='||question_mark||'
    token_dd['(']='||left_parentheses||'
    token_dd[')']='||right_parentheses||'
    token_dd['--']='||dash||'
    token_dd['\n']='||return||'
    
    return token_dd

"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_tokenize(token_lookup)


Tests Passed

Preprocess all the data and save it

Running the code cell below will preprocess all the data and save it to file.


In [5]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
# Preprocess Training, Validation, and Testing Data
helper.preprocess_and_save_data(data_dir, token_lookup, create_lookup_tables)

Check Point

This is your first checkpoint. If you ever decide to come back to this notebook or have to restart the notebook, you can start from here. The preprocessed data has been saved to disk.


In [6]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
import helper
import numpy as np
import problem_unittests as tests

int_text, vocab_to_int, int_to_vocab, token_dict = helper.load_preprocess()

Build the Neural Network

You'll build the components necessary to build a RNN by implementing the following functions below:

  • get_inputs
  • get_init_cell
  • get_embed
  • build_rnn
  • build_nn
  • get_batches

Check the Version of TensorFlow and Access to GPU


In [7]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
from distutils.version import LooseVersion
import warnings
import tensorflow as tf

# Check TensorFlow Version
assert LooseVersion(tf.__version__) >= LooseVersion('1.0'), 'Please use TensorFlow version 1.0 or newer'
print('TensorFlow Version: {}'.format(tf.__version__))

# Check for a GPU
if not tf.test.gpu_device_name():
    warnings.warn('No GPU found. Please use a GPU to train your neural network.')
else:
    print('Default GPU Device: {}'.format(tf.test.gpu_device_name()))


TensorFlow Version: 1.0.1
Default GPU Device: /gpu:0

Input

Implement the get_inputs() function to create TF Placeholders for the Neural Network. It should create the following placeholders:

  • Input text placeholder named "input" using the TF Placeholder name parameter.
  • Targets placeholder
  • Learning Rate placeholder

Return the placeholders in the following the tuple (Input, Targets, LearingRate)


In [8]:
def get_inputs():
    """
    Create TF Placeholders for input, targets, and learning rate.
    :return: Tuple (input, targets, learning rate)
    """
    # TODO: Implement Function
    inputs_ = tf.placeholder(tf.int32, [None, None], name='input')
    targets_ = tf.placeholder(tf.int32, [None, None], name='targets')
    lr = tf.placeholder(tf.float32, name='learning_rate')
    return inputs_, targets_, lr


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_get_inputs(get_inputs)


Tests Passed

Build RNN Cell and Initialize

Stack one or more BasicLSTMCells in a MultiRNNCell.

  • The Rnn size should be set using rnn_size
  • Initalize Cell State using the MultiRNNCell's zero_state() function
    • Apply the name "initial_state" to the initial state using tf.identity()

Return the cell and initial state in the following tuple (Cell, InitialState)


In [9]:
def get_init_cell(batch_size, rnn_size, keep_prob=0.8, layers = 3):
    """
    Create an RNN Cell and initialize it.
    :param batch_size: Size of batches
    :param rnn_size: Size of RNNs
    :return: Tuple (cell, initialize state)
    """
    # TODO: Implement Function
    lstm = tf.contrib.rnn.BasicLSTMCell(rnn_size)
    lstm_drop = tf.contrib.rnn.DropoutWrapper(lstm, output_keep_prob=keep_prob)
    cell = tf.contrib.rnn.MultiRNNCell([lstm_drop] * layers)
    
    initial_state = tf.identity(cell.zero_state(batch_size, tf.float32), name='initial_state')
    
    
    return cell, initial_state


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_get_init_cell(get_init_cell)


Tests Passed

Word Embedding

Apply embedding to input_data using TensorFlow. Return the embedded sequence.


In [10]:
def get_embed(input_data, vocab_size, embed_dim):
    """
    Create embedding for <input_data>.
    :param input_data: TF placeholder for text input.
    :param vocab_size: Number of words in vocabulary.
    :param embed_dim: Number of embedding dimensions
    :return: Embedded input.
    """
    # TODO: Implement Function
    
    embedding = tf.Variable(tf.random_uniform((vocab_size, embed_dim), -1, 1))
    embed = tf.nn.embedding_lookup(embedding, input_data)
    
    return embed


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_get_embed(get_embed)


Tests Passed

Build RNN

You created a RNN Cell in the get_init_cell() function. Time to use the cell to create a RNN.

Return the outputs and final_state state in the following tuple (Outputs, FinalState)


In [11]:
def build_rnn(cell, inputs):
    """
    Create a RNN using a RNN Cell
    :param cell: RNN Cell
    :param inputs: Input text data
    :return: Tuple (Outputs, Final State)
    """
    # TODO: Implement Function    
    outputs, final_state = tf.nn.dynamic_rnn(cell, inputs, dtype=tf.float32)
    final_state = tf.identity(final_state, name='final_state')
    
    return outputs, final_state


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_build_rnn(build_rnn)


Tests Passed

Build the Neural Network

Apply the functions you implemented above to:

  • Apply embedding to input_data using your get_embed(input_data, vocab_size, embed_dim) function.
  • Build RNN using cell and your build_rnn(cell, inputs) function.
  • Apply a fully connected layer with a linear activation and vocab_size as the number of outputs.

Return the logits and final state in the following tuple (Logits, FinalState)


In [12]:
def build_nn(cell, rnn_size, input_data, vocab_size):
    """
    Build part of the neural network
    :param cell: RNN cell
    :param rnn_size: Size of rnns
    :param input_data: Input data
    :param vocab_size: Vocabulary size
    :return: Tuple (Logits, FinalState)
    """
    # TODO: Implement Function
    #print(vocab_size)
    #print(rnn_size)
    embed = get_embed(input_data, vocab_size, rnn_size)
    
    outputs, FinalState = build_rnn(cell, embed)
    
    #print(outputs.shape)
    Logits = tf.contrib.layers.fully_connected(outputs, vocab_size, activation_fn=None)
    
    
    return Logits, FinalState


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_build_nn(build_nn)


Tests Passed

Batches

Implement get_batches to create batches of input and targets using int_text. The batches should be a Numpy array with the shape (number of batches, 2, batch size, sequence length). Each batch contains two elements:

  • The first element is a single batch of input with the shape [batch size, sequence length]
  • The second element is a single batch of targets with the shape [batch size, sequence length]

If you can't fill the last batch with enough data, drop the last batch.

For exmple, get_batches([1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15], 2, 3) would return a Numpy array of the following:

[
  # First Batch
  [
    # Batch of Input
    [[ 1  2  3], [ 7  8  9]],
    # Batch of targets
    [[ 2  3  4], [ 8  9 10]]
  ],

  # Second Batch
  [
    # Batch of Input
    [[ 4  5  6], [10 11 12]],
    # Batch of targets
    [[ 5  6  7], [11 12 13]]
  ]
]

In [13]:
def get_batches(int_text, batch_size, seq_length):
    """
    Return batches of input and target
    :param int_text: Text with the words replaced by their ids
    :param batch_size: The size of batch
    :param seq_length: The length of sequence
    :return: Batches as a Numpy array
    """
    # TODO: Implement Function
    #print(int_text)
    
    batch_seq = batch_size * seq_length
    
    n_batches = len(int_text) // batch_seq
    
    trunc_size = n_batches * batch_seq
        
    out = []
                    
    for i in range(n_batches):
        input_ = []
        target_ = []
        
        for j in range(batch_size):
            start_pos = i * seq_length + j * seq_length
            end_pos = start_pos +  seq_length     
            input_.append(int_text[start_pos : end_pos])
            target_.append(int_text[start_pos + 1 : end_pos + 1])
                    
        out.append([input_, target_])
    
    
    return np.array(out)





"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_get_batches(get_batches)


Tests Passed

Neural Network Training

Hyperparameters

Tune the following parameters:

  • Set num_epochs to the number of epochs.
  • Set batch_size to the batch size.
  • Set rnn_size to the size of the RNNs.
  • Set seq_length to the length of sequence.
  • Set learning_rate to the learning rate.
  • Set show_every_n_batches to the number of batches the neural network should print progress.

In [14]:
# Number of Epochs
num_epochs = 300
# Batch Size
batch_size = 128
# RNN Size
rnn_size = 256
# Sequence Length
seq_length = 30
# Learning Rate
learning_rate = 0.003
# Show stats for every n number of batches
show_every_n_batches = 50

"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
save_dir = './save'

Build the Graph

Build the graph using the neural network you implemented.


In [15]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
from tensorflow.contrib import seq2seq

train_graph = tf.Graph()
with train_graph.as_default():
    vocab_size = len(int_to_vocab)
    input_text, targets, lr = get_inputs()
    input_data_shape = tf.shape(input_text)
    cell, initial_state = get_init_cell(input_data_shape[0], rnn_size)
    logits, final_state = build_nn(cell, rnn_size, input_text, vocab_size)

    # Probabilities for generating words
    probs = tf.nn.softmax(logits, name='probs')

    # Loss function
    cost = seq2seq.sequence_loss(
        logits,
        targets,
        tf.ones([input_data_shape[0], input_data_shape[1]]))

    # Optimizer
    optimizer = tf.train.AdamOptimizer(lr)

    # Gradient Clipping
    gradients = optimizer.compute_gradients(cost)
    capped_gradients = [(tf.clip_by_value(grad, -1., 1.), var) for grad, var in gradients]
    train_op = optimizer.apply_gradients(capped_gradients)

Train

Train the neural network on the preprocessed data. If you have a hard time getting a good loss, check the forms to see if anyone is having the same problem.


In [16]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
batches = get_batches(int_text, batch_size, seq_length)

with tf.Session(graph=train_graph) as sess:
    sess.run(tf.global_variables_initializer())

    for epoch_i in range(num_epochs):
        state = sess.run(initial_state, {input_text: batches[0][0]})

        for batch_i, (x, y) in enumerate(batches):
            feed = {
                input_text: x,
                targets: y,
                initial_state: state,
                lr: learning_rate}
            train_loss, state, _ = sess.run([cost, final_state, train_op], feed)

            # Show every <show_every_n_batches> batches
            if (epoch_i * len(batches) + batch_i) % show_every_n_batches == 0:
                print('Epoch {:>3} Batch {:>4}/{}   train_loss = {:.3f}'.format(
                    epoch_i,
                    batch_i,
                    len(batches),
                    train_loss))

    # Save Model
    saver = tf.train.Saver()
    saver.save(sess, save_dir)
    print('Model Trained and Saved')


Epoch   0 Batch    0/17   train_loss = 8.821
Epoch   2 Batch   16/17   train_loss = 5.387
Epoch   5 Batch   15/17   train_loss = 5.291
Epoch   8 Batch   14/17   train_loss = 5.187
Epoch  11 Batch   13/17   train_loss = 5.097
Epoch  14 Batch   12/17   train_loss = 4.946
Epoch  17 Batch   11/17   train_loss = 4.799
Epoch  20 Batch   10/17   train_loss = 4.613
Epoch  23 Batch    9/17   train_loss = 4.316
Epoch  26 Batch    8/17   train_loss = 3.862
Epoch  29 Batch    7/17   train_loss = 3.445
Epoch  32 Batch    6/17   train_loss = 3.071
Epoch  35 Batch    5/17   train_loss = 2.690
Epoch  38 Batch    4/17   train_loss = 2.260
Epoch  41 Batch    3/17   train_loss = 1.875
Epoch  44 Batch    2/17   train_loss = 1.505
Epoch  47 Batch    1/17   train_loss = 1.202
Epoch  50 Batch    0/17   train_loss = 0.987
Epoch  52 Batch   16/17   train_loss = 0.798
Epoch  55 Batch   15/17   train_loss = 0.621
Epoch  58 Batch   14/17   train_loss = 0.498
Epoch  61 Batch   13/17   train_loss = 0.416
Epoch  64 Batch   12/17   train_loss = 0.326
Epoch  67 Batch   11/17   train_loss = 0.271
Epoch  70 Batch   10/17   train_loss = 0.235
Epoch  73 Batch    9/17   train_loss = 0.211
Epoch  76 Batch    8/17   train_loss = 0.169
Epoch  79 Batch    7/17   train_loss = 0.150
Epoch  82 Batch    6/17   train_loss = 0.131
Epoch  85 Batch    5/17   train_loss = 0.120
Epoch  88 Batch    4/17   train_loss = 0.115
Epoch  91 Batch    3/17   train_loss = 0.097
Epoch  94 Batch    2/17   train_loss = 0.090
Epoch  97 Batch    1/17   train_loss = 0.096
Epoch 100 Batch    0/17   train_loss = 0.088
Epoch 102 Batch   16/17   train_loss = 0.092
Epoch 105 Batch   15/17   train_loss = 0.076
Epoch 108 Batch   14/17   train_loss = 0.065
Epoch 111 Batch   13/17   train_loss = 0.065
Epoch 114 Batch   12/17   train_loss = 0.063
Epoch 117 Batch   11/17   train_loss = 0.058
Epoch 120 Batch   10/17   train_loss = 0.055
Epoch 123 Batch    9/17   train_loss = 0.052
Epoch 126 Batch    8/17   train_loss = 0.047
Epoch 129 Batch    7/17   train_loss = 0.047
Epoch 132 Batch    6/17   train_loss = 0.048
Epoch 135 Batch    5/17   train_loss = 0.045
Epoch 138 Batch    4/17   train_loss = 0.045
Epoch 141 Batch    3/17   train_loss = 0.045
Epoch 144 Batch    2/17   train_loss = 0.045
Epoch 147 Batch    1/17   train_loss = 0.043
Epoch 150 Batch    0/17   train_loss = 0.050
Epoch 152 Batch   16/17   train_loss = 0.047
Epoch 155 Batch   15/17   train_loss = 0.045
Epoch 158 Batch   14/17   train_loss = 0.039
Epoch 161 Batch   13/17   train_loss = 0.039
Epoch 164 Batch   12/17   train_loss = 0.040
Epoch 167 Batch   11/17   train_loss = 0.038
Epoch 170 Batch   10/17   train_loss = 0.037
Epoch 173 Batch    9/17   train_loss = 0.037
Epoch 176 Batch    8/17   train_loss = 0.036
Epoch 179 Batch    7/17   train_loss = 0.036
Epoch 182 Batch    6/17   train_loss = 0.034
Epoch 185 Batch    5/17   train_loss = 0.037
Epoch 188 Batch    4/17   train_loss = 0.035
Epoch 191 Batch    3/17   train_loss = 0.035
Epoch 194 Batch    2/17   train_loss = 0.037
Epoch 197 Batch    1/17   train_loss = 0.033
Epoch 200 Batch    0/17   train_loss = 0.036
Epoch 202 Batch   16/17   train_loss = 0.038
Epoch 205 Batch   15/17   train_loss = 0.036
Epoch 208 Batch   14/17   train_loss = 0.033
Epoch 211 Batch   13/17   train_loss = 0.033
Epoch 214 Batch   12/17   train_loss = 0.033
Epoch 217 Batch   11/17   train_loss = 0.031
Epoch 220 Batch   10/17   train_loss = 0.031
Epoch 223 Batch    9/17   train_loss = 0.031
Epoch 226 Batch    8/17   train_loss = 0.030
Epoch 229 Batch    7/17   train_loss = 0.030
Epoch 232 Batch    6/17   train_loss = 0.031
Epoch 235 Batch    5/17   train_loss = 0.030
Epoch 238 Batch    4/17   train_loss = 0.034
Epoch 241 Batch    3/17   train_loss = 0.030
Epoch 244 Batch    2/17   train_loss = 0.032
Epoch 247 Batch    1/17   train_loss = 0.030
Epoch 250 Batch    0/17   train_loss = 0.033
Epoch 252 Batch   16/17   train_loss = 0.036
Epoch 255 Batch   15/17   train_loss = 0.032
Epoch 258 Batch   14/17   train_loss = 0.031
Epoch 261 Batch   13/17   train_loss = 0.030
Epoch 264 Batch   12/17   train_loss = 0.029
Epoch 267 Batch   11/17   train_loss = 0.030
Epoch 270 Batch   10/17   train_loss = 0.030
Epoch 273 Batch    9/17   train_loss = 0.029
Epoch 276 Batch    8/17   train_loss = 0.028
Epoch 279 Batch    7/17   train_loss = 0.029
Epoch 282 Batch    6/17   train_loss = 0.028
Epoch 285 Batch    5/17   train_loss = 0.028
Epoch 288 Batch    4/17   train_loss = 0.032
Epoch 291 Batch    3/17   train_loss = 0.036
Epoch 294 Batch    2/17   train_loss = 0.035
Epoch 297 Batch    1/17   train_loss = 0.030
Model Trained and Saved

Save Parameters

Save seq_length and save_dir for generating a new TV script.


In [17]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
# Save parameters for checkpoint
helper.save_params((seq_length, save_dir))

Checkpoint


In [18]:
"""
DON'T MODIFY ANYTHING IN THIS CELL
"""
import tensorflow as tf
import numpy as np
import helper
import problem_unittests as tests

_, vocab_to_int, int_to_vocab, token_dict = helper.load_preprocess()
seq_length, load_dir = helper.load_params()

Implement Generate Functions

Get Tensors

Get tensors from loaded_graph using the function get_tensor_by_name(). Get the tensors using the following names:

  • "input:0"
  • "initial_state:0"
  • "final_state:0"
  • "probs:0"

Return the tensors in the following tuple (InputTensor, InitialStateTensor, FinalStateTensor, ProbsTensor)


In [19]:
def get_tensors(loaded_graph):
    """
    Get input, initial state, final state, and probabilities tensor from <loaded_graph>
    :param loaded_graph: TensorFlow graph loaded from file
    :return: Tuple (InputTensor, InitialStateTensor, FinalStateTensor, ProbsTensor)
    """
    # TODO: Implement Function
    
    inputs = loaded_graph.get_tensor_by_name('input:0')
    initial_state = loaded_graph.get_tensor_by_name('initial_state:0')
    final_state = loaded_graph.get_tensor_by_name('final_state:0')
    probs = loaded_graph.get_tensor_by_name('probs:0')
    
    return inputs, initial_state, final_state, probs


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_get_tensors(get_tensors)


Tests Passed

Choose Word

Implement the pick_word() function to select the next word using probabilities.


In [20]:
def pick_word(probabilities, int_to_vocab):
    """
    Pick the next word in the generated text
    :param probabilities: Probabilites of the next word
    :param int_to_vocab: Dictionary of word ids as the keys and words as the values
    :return: String of the predicted word
    """
    # TODO: Implement Function
    return int_to_vocab[np.argmax(probabilities)]


"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
tests.test_pick_word(pick_word)


Tests Passed

Generate TV Script

This will generate the TV script for you. Set gen_length to the length of TV script you want to generate.


In [21]:
gen_length = 200
# homer_simpson, moe_szyslak, or Barney_Gumble
prime_word = 'moe_szyslak'

"""
DON'T MODIFY ANYTHING IN THIS CELL THAT IS BELOW THIS LINE
"""
loaded_graph = tf.Graph()
with tf.Session(graph=loaded_graph) as sess:
    # Load saved model
    loader = tf.train.import_meta_graph(load_dir + '.meta')
    loader.restore(sess, load_dir)

    # Get Tensors from loaded model
    input_text, initial_state, final_state, probs = get_tensors(loaded_graph)

    # Sentences generation setup
    gen_sentences = [prime_word + ':']
    prev_state = sess.run(initial_state, {input_text: np.array([[1]])})

    # Generate sentences
    for n in range(gen_length):
        # Dynamic Input
        dyn_input = [[vocab_to_int[word] for word in gen_sentences[-seq_length:]]]
        dyn_seq_length = len(dyn_input[0])

        # Get Prediction
        probabilities, prev_state = sess.run(
            [probs, final_state],
            {input_text: dyn_input, initial_state: prev_state})
        
        pred_word = pick_word(probabilities[dyn_seq_length-1], int_to_vocab)

        gen_sentences.append(pred_word)
    
    # Remove tokens
    tv_script = ' '.join(gen_sentences)
    for key, token in token_dict.items():
        ending = ' ' if key in ['\n', '(', '"'] else ''
        tv_script = tv_script.replace(' ' + token.lower(), key)
    tv_script = tv_script.replace('\n ', '\n')
    tv_script = tv_script.replace('( ', '(')
        
    print(tv_script)


moe_szyslak: minimum wage and tips.(meaningfully) of course there are fringe benefits.
collette: such as?
moe_szyslak: an unforgettable weekend at club moe.
homer_simpson:(quietly. your money think moe and does the beer," seconds left to mcstagger..
moe_szyslak: no" flaming homer..
football_announcer: a doll, spot you was us for a little money.. if moe_szyslak: great to try that pal.(his hair, marvelous out of on for my problems, hundred?
moe_szyslak: you not fire.
moe_szyslak:(musses nose. for your) down.(uh, great spectacular.
moe_szyslak:(are on for marvelous in down.
homer_simpson: hi barney. pit the barkeep is the does your handoff.
moe_szyslak:(loud) what's on, how all right, denver. justify my love.
moe_szyslak: what think i can't the here you get. it know, care i just my new all great you musses cough"
moe_szyslak: hey. i shut there.. nobody think you got is and

The TV Script is Nonsensical

It's ok if the TV script doesn't make any sense. We trained on less than a megabyte of text. In order to get good results, you'll have to use a smaller vocabulary or get more data. Luckly there's more data! As we mentioned in the begging of this project, this is a subset of another dataset. We didn't have you train on all the data, because that would take too long. However, you are free to train your neural network on all the data. After you complete the project, of course.

Submitting This Project

When submitting this project, make sure to run all the cells before saving the notebook. Save the notebook file as "dlnd_tv_script_generation.ipynb" and save it as a HTML file under "File" -> "Download as". Include the "helper.py" and "problem_unittests.py" files in your submission.