def BoundaryToCentre(bin_bounds):
    """
    BoundaryToCentre - converts coordinates for edges of bins to centre of bin coordinates

    Parameters
    ----------
        bin_bounds: 1d np array  
                    Edge coordinates of each bin

    Returns
    -------
        bin_centres: 1d np narray of length 1 less than bin_bounds
                    Coordinates at centre of bin
    """
    half_width = (bin_bounds[1] - bin_bounds[0]) / 2
    bin_centers = bin_bounds[:len(bin_bounds) - 1] + half_width
    return bin_centers
