def robotsrulesetOfDomain(self, domain):
		'''检查domain是否在数据库中,
			否 --> (False, None)
			是 --> (True, 数据库中存储的robots.txt内容)
		'''
		exist = False
		cur = self.conn.cursor()
		# 是否存在
		cur.execute("SELECT 1 FROM Domains WHERE domain=?", (domain,))
		if cur.fetchone() :
			exist = True
		# 存在的话,结果是什么
		cur.execute("SELECT rules FROM Domains,Rulesets "
			"WHERE domain=? AND Domains.did=Rulesets.did"
			,(domain,) )
		ruleset = cur.fetchone()
		return (exist, ruleset)
def demag_pos(isa, pos, icur=-1, ibeta=-1, ax=0):
    """plot demag of NC/I7/ISA7 model at rotor position
    Args:
      isa: Isa7/NC object
      pos: rotor position in degree
      icur: cur amplitude index or last index if -1
      ibeta: beta angle index or last index if -1
    """
    emag = [e for e in isa.elements if e.is_magnet()]
    demag = np.array([isa.demagnetization(e, icur, ibeta)[1]
                     for e in emag])
    for i, x in enumerate(isa.pos_el_fe_induction):
        if x >= pos/180*np.pi:
            break

    hpol = demag[:, i]
    hpol[hpol == 0] = np.nan
    _contour(ax, f'Demagnetization at Pos. {round(x/np.pi*180)}° ({isa.MAGN_TEMPERATURE} °C)',
             emag, hpol, '-H / kA/m', isa)
    logger.info("Max demagnetization %f kA/m", np.nanmax(hpol))