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# scipy.stats.itemfreq

`scipy.stats.``itemfreq`(a)

  Returns a 2D array of item frequencies.

  Parameters : | a : (N,) array_like Input array.
  Returns : | itemfreq : (2,K) ndarray A 2D frequency table (col [0:n-1]=scores, col n=frequencies). Column 1 contains sorted, unique values from a, column 2 contains their respective counts.

  Notes

  This uses a loop that is only reasonably fast if the number of unique elements is not large. For integers, numpy.bincount is much faster. This function currently does not support strings or multi-dimensional scores.

  Examples

      >>> a = np.array([1, 1, 5, 0, 1, 2, 2, 0, 1, 4])
      >>> stats.itemfreq(a)
      array([[ 0.,  2.],
             [ 1.,  4.],
             [ 2.,  2.],
             [ 4.,  1.],
             [ 5.,  1.]])
      >>> np.bincount(a)
      array([2, 4, 2, 0, 1, 1])

      >>> stats.itemfreq(a/10.)
      array([[ 0. ,  2. ],
             [ 0.1,  4. ],
             [ 0.2,  2. ],
             [ 0.4,  1. ],
             [ 0.5,  1. ]])

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