def METHOD_NAME(rj, ri, h):
    sigj = rj/h
    sigi = ri/h
    sigdiff = abs(sigj - sigi)
    sigplus = sigj + sigi
    sgndiff = sgn0(sigi - sigj)
    if sigplus <= 1.0:
        return -W3S1(rj, ri, h)/ri + (gradC(sigplus) - gradC(sigdiff)*sgndiff)/(h*h*ri*rj)
    elif sigplus <= 2.0:
        if sigdiff < 1.0:
            return -W3S1(rj, ri, h)/ri + (gradD(sigplus) - gradC(sigdiff)*sgndiff)/(h*h*ri*rj)
        else:
            return -W3S1(rj, ri, h)/ri + (gradD(sigplus) - gradD(sigdiff)*sgndiff)/(h*h*ri*rj)
    else:
        if sigdiff < 1.0:
            return -W3S1(rj, ri, h)/ri - gradC(sigdiff)*sgndiff/(h*h*ri*rj)
        else:
            return -W3S1(rj, ri, h)/ri - gradD(sigdiff)*sgndiff/(h*h*ri*rj)