def dfunc(self,v,r,j):
        if v == 0:
            return 0
        elif v == 1:
            return ( j+1 )
        elif v == 2:
            return ( (j+2) + 2.*(j*j+ 4.*j+ 3.)/3.*r )
        elif v == 3:
            return ( (j+3) + 2.*(6.*j*j+36.*j+45.)/15.*r + 5.*r*r/(j*j*j+9.*j*j+23.*j+15.) )
        else:
            raise Exception (["Wrong degree in PiecePoly.  Should be 0,1,2 or 3, is " + str(v)])
dataset/ETHPy150Open marionmari/pyGPs/pyGPs/Core/cov.py/PiecePoly.dfunc/swapped operands of `/`