def _Psi_line(self,s,dalpha,alpha,K,m,likfunc,y,inffunc):
        '''Criterion Psi at alpha + s*dalpha for line search
        [Psi,alpha,f,dlp,W] = _Psi_line(s,dalpha,alpha,hyp,K,m,lik,y,inf)
        '''
        alpha = alpha + s*dalpha
        f = np.dot(K,alpha) + m
        [lp,dlp,d2lp] = likfunc.evaluate(y,f,None,inffunc,None,3)
        W = -d2lp
        Psi = lp.sum() - old_div(np.dot(alpha.T,(f-m)),2.)
        return Psi[0],alpha,f,dlp,W
dataset/ETHPy150Open marionmari/pyGPs/pyGPs/Core/inf.py/Inference._Psi_line/swapped operands of `-`