cosmology.py 文件源码

def Dm(self, z, cm=False, meter=False, pc=False, kpc=False, mpc=False):
        Ok  = self.Ok()
        sOk = num.sqrt(num.abs(Ok))
        Dc  = self.Dc(z)
        Dh  = self.Dh()

        conversion = self.lengthConversion(cm=cm, meter=meter, pc=pc, kpc=kpc, mpc=mpc)

        if Ok > 0:
            return Dh / sOk * num.sinh(sOk * Dc / Dh) * conversion
        elif Ok == 0:
            return Dc * conversion
        else:
            return Dh / sOk * num.sin(sOk * Dc / Dh) * conversion

    # Angular diameter distance
    # Ratio of an objects physical transvserse size to its angular size in radians