def plot_err(x, y, dy, fy, view=None, **kw):
    """
    **DEPRECATED**: subclass Curve and override the plot function.

    Plot data *y* and error *dy* against *x*.

    *view* is one of linear, log, logx or loglog.
    """
    import pylab
    pylab.errorbar(x, y, yerr=dy, fmt='.')
    pylab.plot(x, fy, '-')
    if view == 'log':
        pylab.xscale('linear')
        pylab.yscale('log')
    elif view == 'logx':
        pylab.xscale('log')
        pylab.yscale('linear')
    elif view == 'loglog':
        pylab.xscale('log')
        pylab.yscale('log')
    else:
        pylab.xscale('linear')
        pylab.yscale('linear')
