title: Incremental Word2Vec Model Training in gensim
body: <p>I have tried to train incrementally  word2vec model produced by gensim. But I found that the vocabulary size doesn't increased , only the word2vec model weights are updated . But i need to  update both vocabulary and model size .</p>
  
  <pre><code>#Load data 
  sentences = []
  ....................
  
  #Training 
  model = Word2Vec(sentences, size=100)
  model.save("modelbygensim.txt")
  model.save_word2vec_format("modelbygensim_text.txt")
  
  
  
  #Incremental Training 
  model = Word2Vec.load('modelbygensim.txt')
  model.train(sentences)
  model.save("modelbygensim_incremental.txt")
  model.save_word2vec_format("modelbygensim_text_incremental.txt")
  </code></pre>