ó šßÈ[c@`szdZddlmZmZmZmZddlZddlm Z dgZ idgd6Z d e j fd „ƒYZdS( u` This module contains the classes and utility functions for distance and cartesian coordinates. i(tabsolute_importtdivisiontprint_functiontunicode_literalsNi(tunitsuDistanceuscipy.integrateu*tDistancec B`s€eZdZejZeZddddddede de d„ Z e d„ƒZ dd„Z e d„ƒZed„ƒZRS(uÞ A one-dimensional distance. This can be initialized in one of four ways: * A distance ``value`` (array or float) and a ``unit`` * A `~astropy.units.Quantity` object * A redshift and (optionally) a cosmology. * Providing a distance modulus Parameters ---------- value : scalar or `~astropy.units.Quantity`. The value of this distance. unit : `~astropy.units.UnitBase` The units for this distance, *if* ``value`` is not a `~astropy.units.Quantity`. Must have dimensions of distance. z : float A redshift for this distance. It will be converted to a distance by computing the luminosity distance for this redshift given the cosmology specified by ``cosmology``. Must be given as a keyword argument. cosmology : ``Cosmology`` or `None` A cosmology that will be used to compute the distance from ``z``. If `None`, the current cosmology will be used (see `astropy.cosmology` for details). distmod : float or `~astropy.units.Quantity` The distance modulus for this distance. Note that if ``unit`` is not provided, a guess will be made at the unit between AU, pc, kpc, and Mpc. dtype : `~numpy.dtype`, optional See `~astropy.units.Quantity`. copy : bool, optional See `~astropy.units.Quantity`. order : {'C', 'F', 'A'}, optional See `~astropy.units.Quantity`. subok : bool, optional See `~astropy.units.Quantity`. ndmin : int, optional See `~astropy.units.Quantity`. allow_negative : bool, optional Whether to allow negative distances (which are possible is some cosmologies). Default: ``False``. Raises ------ `~astropy.units.UnitsError` If the ``unit`` is not a distance. ValueError If value specified is less than 0 and ``allow_negative=False``. If ``z`` is provided with a ``unit`` or ``cosmology`` is provided when ``z`` is *not* given, or ``value`` is given as well as ``z``. Examples -------- >>> from astropy import units as u >>> from astropy import cosmology >>> from astropy.cosmology import WMAP5, WMAP7 >>> cosmology.set_current(WMAP7) >>> d1 = Distance(10, u.Mpc) >>> d2 = Distance(40, unit=u.au) >>> d3 = Distance(value=5, unit=u.kpc) >>> d4 = Distance(z=0.23) >>> d5 = Distance(z=0.23, cosmology=WMAP5) >>> d6 = Distance(distmod=24.47) >>> d7 = Distance(Distance(10 * u.Mpc)) ic C`sÑ|dk rv|dk s$|dk r3tdƒ‚n|dkr^ddlm} | jƒ}n|j|ƒ}t}ní|dk r‘tdƒ‚n|dk rH|dk r¸tdƒ‚n|j|ƒ}|dkr?tj |j ƒj ƒ} | dkrt j }q?| dkrt j}q?| dkr3t j}q?t j}nt}n|dkrctdƒ‚ntt|ƒj|||d |d |d |d | d | ƒ}| rÍtj|j dkƒrÍtdƒ‚n|S(NuKShould given only one of `value`, `z` or `distmod` in Distance constructor.i(tdefault_cosmologyuHA `cosmology` was given but `z` was not provided in Distance constructoriiiýÿÿÿuENone of `value`, `z`, or `distmod` were given to Distance constructortdtypetcopytordertsuboktndminiuXDistance must be >= 0. Use the argument 'allow_negative=True' to allow negative values.(tNonet ValueErrort cosmologyRtgettluminosity_distancetFalset_distmod_to_pctnptlog10tvaluetmeantutMpctkpctAUtpctsuperRt__new__tany(tclsRtunittzRtdistmodRRR R R tallow_negativeRt meanlogvaltdistance((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyR]s@                cC`s |jƒS(uShort for ``self.compute_z()``(t compute_z(tself((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyR!šscC`sQ|dkr+ddlm}|jƒ}nddlm}||j|ddƒS(u× The redshift for this distance assuming its physical distance is a luminosity distance. Parameters ---------- cosmology : ``Cosmology`` or `None` The cosmology to assume for this calculation, or `None` to use the current cosmology (see `astropy.cosmology` for details). Returns ------- z : float The redshift of this distance given the provided ``cosmology``. i(R(t z_at_valuetztolg»½×Ùß|Û=N(R RRRR(R(R'RRR(((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyR&Ÿs  cC`s<dtj|jtjƒƒd}tj|tjdtƒS(u3The distance modulus as a `~astropy.units.Quantity`g@R(RRtto_valueRRtQuantitytmagR(R'tval((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyR"·s#cC`s:tj|tjƒ}|d|jddtjdtƒS(Ni ig@R(RR+R,RRR(Rtdm((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyR½sN(t__name__t __module__t__doc__Rtmt_equivalent_unittTruet _include_easy_conversion_membersR RRtpropertyR!R&R"t classmethodR(((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyRsD   ; (R1t __future__RRRRtnumpyRtRRt__all__t__doctest_requires__tSpecificTypeQuantityR(((s<lib/python2.7/site-packages/astropy/coordinates/distances.pyts "