def _get_flim(flim, fscale, freq, sfreq=None):
    'Get reasonable frequency limits.'
    if (flim is None):
        if (freq is None):
            flim = [(0.1 if (fscale == 'log') else 0.0), (sfreq / 2.0)]
        else:
            if (fscale == 'linear'):
                flim = [freq[0]]
            else:
                flim = [(freq[0] if (freq[0] > 0) else (0.1 * freq[1]))]
            flim += [freq[(- 1)]]
    if (fscale == 'log'):
        if (flim[0] <= 0):
            raise ValueError(('flim[0] must be positive, got %s' % flim[0]))
    elif (flim[0] < 0):
        raise ValueError(('flim[0] must be non-negative, got %s' % flim[0]))
    return flim
Get reasonable frequency limits.
def _get_flim(flim, fscale, freq, sfreq=None):
    
    if (flim is None):
        if (freq is None):
            flim = [(0.1 if (fscale == 'log') else 0.0), (sfreq / 2.0)]
        else:
            if (fscale == 'linear'):
                flim = [freq[0]]
            else:
                flim = [(freq[0] if (freq[0] > 0) else (0.1 * freq[1]))]
            flim += [freq[(- 1)]]
    if (fscale == 'log'):
        if (flim[0] <= 0):
            raise ValueError(('flim[0] must be positive, got %s' % flim[0]))
    elif (flim[0] < 0):
        raise ValueError(('flim[0] must be non-negative, got %s' % flim[0]))
    return flim