text: Title: Negative exponent with value -1 (minus one) raises error when loading Doc2Vec model
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  #### Problem description
  
  I try to vary the value of the negative exponent parameter. When I use a value of -1, training works fine, saving the model too, but when I try to load the model afterwards with Doc2Vec.load() it raises the error "ValueError: Integers to negative integer powers are not allowed."
  
  This is due to the following line: https://github.com/RaRe-Technologies/gensim/blob/266a01455ade51a93a08dba5950e87b4d98e0724/gensim/models/word2vec.py#L836
  
  Here, numpy does not raise an integer by the power of another, but negative integer.
  
  I guess this could be solved by converting the exponent to a float in this case?
  
  
  