# scipy.spatial.distance.russellrao

scipy.spatial.distance.russellrao(u, v, w=None)

  Compute the Russell-Rao dissimilarity between two boolean 1-D arrays.

  The Russell-Rao dissimilarity between two boolean 1-D arrays, u and v, is defined as

  \[\frac{n - c_{TT}} {n}\]

  where \(c_{ij}\) is the number of occurrences of \(\mathtt{u[k]} = i\) and \(\mathtt{v[k]} = j\) for \(k < n\).

  Parameters:
    u(N,) array_like, bool

      Input array.

    v(N,) array_like, bool

      Input array.

    w(N,) array_like, optional

      The weights for each value in u and v. Default is None, which gives each value a weight of 1.0

  Returns:
    russellrao double

      The Russell-Rao dissimilarity between vectors u and v.

  Examples

      >>> from scipy.spatial import distance
      >>> distance.russellrao([1, 0, 0], [0, 1, 0])
      1.0
      >>> distance.russellrao([1, 0, 0], [1, 1, 0])
      0.6666666666666666
      >>> distance.russellrao([1, 0, 0], [2, 0, 0])
      0.3333333333333333