def convert_coordinates(q, conversion, axisorder):
    """
    Convert a 3-tuple in data coordinates into to simplex data
    coordinates for plotting.

    Parameters
    ----------
    q: 3-tuple
       the point to be plotted in data coordinates

    conversion: dict
        keys = ['b','l','r']
        values = lambda function giving the conversion
    axisorder: String giving the order of the axes for the coordinate tuple
        e.g. 'blr' for bottom, left, right coordinates.

    Returns
    -------
    p: 3-tuple
       The point converted to simplex coordinates.
    """
    p = []
    for k in range(3):
        p.append(conversion[axisorder[k]](q[k]))
    return tuple(p)
