yablog: calculate cosine with python numpy

yablog: calculate cosine with python numpy

calculate cosine with python numpy

purpose

Calculate “cosine” determined by pair of vectors using python and its package named numpy. Firstly I show you the definition of cosine in linear space, and Secondly I share sample python code for calculating cosine.

definition of cosine in linear space

python code for calculating cosine

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import numpy   def get_cosine(v1, v2):      """ calculate cosine and returns cosine """      n1 = get_norm_of_vector(v1)      n2 = get_norm_of_vector(v2)      ip = get_inner_product(v1, v2)      return ip / (n1 * n2)   def get_inner_product(v1, v2):      """ calculate inner product """      return numpy.dot(v1, v2)   def get_norm_of_vector(v):      """ calculate norm of vector """      return numpy.linalg.norm(v)   def get_radian_from_cosine(cos):      return numpy.arccos(cos)   def get_degrees_from_radian(cos):      return numpy.degrees(cos)   def main():      v1 = numpy.array([ 1 , 0 ])      v2 = numpy.array([ 1 , numpy.sqrt( 3 )])      cosine = get_cosine(v1, v2)      radian = get_radian_from_cosine(cosine)      print get_degrees_from_radian(radian)   if __name__ = = "__main__" :      main()