ó ›ßÈ[c @`s)ddlmZmZmZmZddlZddlmZ ddl m Z ddl m Z mZdgZd d dd d d dddg Zd„Zd„ZeggZdefd„ƒYZd„Zd„Zd„Zdd„Zd„Zd„Zd„Zddd„Zdddd„ZdS( i(tabsolute_importtdivisiontprint_functiontunicode_literalsNi(tunits(trangei(tWCSSUB_LONGITUDEtWCSSUB_LATITUDEuwcs_to_celestial_frameuadd_stokes_axis_to_wcsucustom_frame_mappingsuproj_plane_pixel_scalesuproj_plane_pixel_areauis_proj_plane_distortedunon_celestial_pixel_scalesuskycoord_to_pixelupixel_to_skycoordcC`slgt|jjƒD]}|d^q}|j|dƒ|j|ƒ}d|jj|>> from astropy.wcs.utils import wcs_to_celestial_frame, custom_frame_mappings >>> with custom_frame_mappings(my_function): ... wcs_to_celestial_frame(...) uMCould not determine celestial frame corresponding to the specified WCS objectN(R)Rt ValueError(Rt mapping_settfuncR%((s0lib/python2.7/site-packages/astropy/wcs/utils.pytwcs_to_celestial_framess      cC`s)tj|jdjdddtjƒƒS(u1 For a WCS returns pixel scales along each axis of the image pixel at the ``CRPIX`` location once it is projected onto the "plane of intermediate world coordinates" as defined in `Greisen & Calabretta 2002, A&A, 395, 1061 `_. .. note:: This function is concerned **only** about the transformation "image plane"->"projection plane" and **not** about the transformation "celestial sphere"->"projection plane"->"image plane". Therefore, this function ignores distortions arising due to non-linear nature of most projections. .. note:: In order to compute the scales corresponding to celestial axes only, make sure that the input `~astropy.wcs.WCS` object contains celestial axes only, e.g., by passing in the `~astropy.wcs.WCS.celestial` WCS object. Parameters ---------- wcs : `~astropy.wcs.WCS` A world coordinate system object. Returns ------- scale : `~numpy.ndarray` A vector (`~numpy.ndarray`) of projection plane increments corresponding to each pixel side (axis). The units of the returned results are the same as the units of `~astropy.wcs.Wcsprm.cdelt`, `~astropy.wcs.Wcsprm.crval`, and `~astropy.wcs.Wcsprm.cd` for the celestial WCS and can be obtained by inquiring the value of `~astropy.wcs.Wcsprm.cunit` property of the input `~astropy.wcs.WCS` WCS object. See Also -------- astropy.wcs.utils.proj_plane_pixel_area itaxisitdtype(R!tsqrttpixel_scale_matrixtsumtfloat(R((s0lib/python2.7/site-packages/astropy/wcs/utils.pytproj_plane_pixel_scales™s)cC`sC|jj}|jdkr*tdƒ‚ntjtjj|ƒƒS(uZ For a **celestial** WCS (see `astropy.wcs.WCS.celestial`) returns pixel area of the image pixel at the ``CRPIX`` location once it is projected onto the "plane of intermediate world coordinates" as defined in `Greisen & Calabretta 2002, A&A, 395, 1061 `_. .. note:: This function is concerned **only** about the transformation "image plane"->"projection plane" and **not** about the transformation "celestial sphere"->"projection plane"->"image plane". Therefore, this function ignores distortions arising due to non-linear nature of most projections. .. note:: In order to compute the area of pixels corresponding to celestial axes only, this function uses the `~astropy.wcs.WCS.celestial` WCS object of the input ``wcs``. This is different from the `~astropy.wcs.utils.proj_plane_pixel_scales` function that computes the scales for the axes of the input WCS itself. Parameters ---------- wcs : `~astropy.wcs.WCS` A world coordinate system object. Returns ------- area : float Area (in the projection plane) of the pixel at ``CRPIX`` location. The units of the returned result are the same as the units of the `~astropy.wcs.Wcsprm.cdelt`, `~astropy.wcs.Wcsprm.crval`, and `~astropy.wcs.Wcsprm.cd` for the celestial WCS and can be obtained by inquiring the value of `~astropy.wcs.Wcsprm.cunit` property of the `~astropy.wcs.WCS.celestial` WCS object. Raises ------ ValueError Pixel area is defined only for 2D pixels. Most likely the `~astropy.wcs.Wcsprm.cd` matrix of the `~astropy.wcs.WCS.celestial` WCS is not a square matrix of second order. Notes ----- Depending on the application, square root of the pixel area can be used to represent a single pixel scale of an equivalent square pixel whose area is equal to the area of a generally non-square pixel. See Also -------- astropy.wcs.utils.proj_plane_pixel_scales iu)Pixel area is defined only for 2D pixels.(ii(t celestialR=tshapeR6R!tabstlinalgtdet(Rtpsm((s0lib/python2.7/site-packages/astropy/wcs/utils.pytproj_plane_pixel_areaÅs7 gñh㈵øä>cC`s&|j}t|j|ƒ p%t|ƒS(u– For a WCS returns `False` if square image (detector) pixels stay square when projected onto the "plane of intermediate world coordinates" as defined in `Greisen & Calabretta 2002, A&A, 395, 1061 `_. It will return `True` if transformation from image (detector) coordinates to the focal plane coordinates is non-orthogonal or if WCS contains non-linear (e.g., SIP) distortions. .. note:: Since this function is concerned **only** about the transformation "image plane"->"focal plane" and **not** about the transformation "celestial sphere"->"focal plane"->"image plane", this function ignores distortions arising due to non-linear nature of most projections. Let's denote by *C* either the original or the reconstructed (from ``PC`` and ``CDELT``) CD matrix. `is_proj_plane_distorted` verifies that the transformation from image (detector) coordinates to the focal plane coordinates is orthogonal using the following check: .. math:: \left \| \frac{C \cdot C^{\mathrm{T}}} {| det(C)|} - I \right \|_{\mathrm{max}} < \epsilon . Parameters ---------- wcs : `~astropy.wcs.WCS` World coordinate system object maxerr : float, optional Accuracy to which the CD matrix, **normalized** such that :math:`|det(CD)|=1`, should be close to being an orthogonal matrix as described in the above equation (see :math:`\epsilon`). Returns ------- distorted : bool Returns `True` if focal (projection) plane is distorted and `False` otherwise. (RAt_is_cd_orthogonalR=t_has_distortion(Rtmaxerrtcwcs((s0lib/python2.7/site-packages/astropy/wcs/utils.pytis_proj_plane_distorteds- cC`sÀ|j}t|ƒdko,|d|dks>tdƒ‚ntjtjj|ƒƒ}|dkrttdƒ‚ntj||jƒ|}tj tj|tj |dƒƒƒ}||kS(Niiiu-CD (or PC) matrix must be a 2D square matrix.guCD (or PC) matrix is singular.( RBtlenR6R!RCRDREtdottTtamaxteye(tcdRJRBtpixareatItcd_unitary_err((s0lib/python2.7/site-packages/astropy/wcs/utils.pyRH4s & )cC`s||jrtdƒ‚n|j}tjtjdtj|jŒ|ƒdƒrltjtj |ƒƒt j Stdƒ‚dS(uM Calculate the pixel scale along each axis of a non-celestial WCS, for example one with mixed spectral and spatial axes. Parameters ---------- inwcs : `~astropy.wcs.WCS` The world coordinate system object. Returns ------- scale : `numpy.ndarray` The pixel scale along each axis. u4WCS is celestial, use celestial_pixel_scales insteadiiu8WCS is rotated, cannot determine consistent pixel scalesN( t is_celestialR6R=R!tallclosetextractRQRBRCtdiagonaltutdeg(tinwcstpccd((s0lib/python2.7/site-packages/astropy/wcs/utils.pytnon_celestial_pixel_scalesEs   .c`s)t‡fd†dddddgDƒƒS(uD `True` if contains any SIP or image distortion components. c3`s$|]}tˆ|ƒdk VqdS(N(tgetattrR(t.0t dist_attr(R(s0lib/python2.7/site-packages/astropy/wcs/utils.pys dsucpdis1ucpdis2udet2im1udet2im2usip(tany(R((Rs0lib/python2.7/site-packages/astropy/wcs/utils.pyRI`suallc C`s¬ddlm}ddlm}t|ƒrJ|jdkrJtdƒ‚n|jttgƒ}|jdkr}tdƒ‚nt |ƒ}|j |j j dƒ}|j |j j dƒ}|j |ƒ}y.|jjj|ƒ} |jjj|ƒ} Wn;tk r5|jjj|ƒ} |jjj|ƒ} nX|dkrf|j| j| j|ƒ\} } n<|d kr–|j| j| j|ƒ\} } n td ƒ‚| | fS( uƒ Convert a set of SkyCoord coordinates into pixels. Parameters ---------- coords : `~astropy.coordinates.SkyCoord` The coordinates to convert. wcs : `~astropy.wcs.WCS` The WCS transformation to use. origin : int Whether to return 0 or 1-based pixel coordinates. mode : 'all' or 'wcs' Whether to do the transformation including distortions (``'all'``) or only including only the core WCS transformation (``'wcs'``). Returns ------- xp, yp : `numpy.ndarray` The pixel coordinates See Also -------- astropy.coordinates.SkyCoord.from_pixel i(Ri(tWCSSUB_CELESTIALu:Can only handle WCS with distortions for 2-dimensional WCSu&WCS should contain celestial componentiualluwcsu$mode should be either 'all' or 'wcs'(tRRcRIR R6R RRR9tUnitRtcunitt transform_totdatatlonttoRtAttributeErrort sphericalt all_world2pixR1t wcs_world2pix( tcoordsRtorigintmodeRZRcR%txw_unittyw_unitRiRtxptyp((s0lib/python2.7/site-packages/astropy/wcs/utils.pytskycoord_to_pixelks.   $ $ cC`sˆddlm}ddlm}ddlm}m} |dkrK|}nt|ƒru|jdkrut dƒ‚n|j t t gƒ}|jdkr¨t dƒ‚nt |ƒ} |j|jjdƒ} |j|jjdƒ} |d kr|j|||ƒ\} }n6|d kr:|j|||ƒ\} }n t d ƒ‚| | } || }| d | d |ƒ}|| j|ƒƒ}|S(u˜ Convert a set of pixel coordinates into a `~astropy.coordinates.SkyCoord` coordinate. Parameters ---------- xp, yp : float or `numpy.ndarray` The coordinates to convert. wcs : `~astropy.wcs.WCS` The WCS transformation to use. origin : int Whether to return 0 or 1-based pixel coordinates. mode : 'all' or 'wcs' Whether to do the transformation including distortions (``'all'``) or only including only the core WCS transformation (``'wcs'``). cls : class or None The class of object to create. Should be a `~astropy.coordinates.SkyCoord` subclass. If None, defaults to `~astropy.coordinates.SkyCoord`. Returns ------- coords : Whatever ``cls`` is (a subclass of `~astropy.coordinates.SkyCoord`) The celestial coordinates See Also -------- astropy.coordinates.SkyCoord.from_pixel i(Ri(Rc(tSkyCoordtUnitSphericalRepresentationu:Can only handle WCS with distortions for 2-dimensional WCSu&WCS should contain celestial componentiualluwcsu$mode should be either 'all' or 'wcs'RiRN(RdRRcRRwRxRRIR R6R RRR9ReRRft all_pix2worldt wcs_pix2worldt realize_frame(RtRuRRpRqtclsRZRcRwRxR%tlon_unittlat_unitRiRRhRo((s0lib/python2.7/site-packages/astropy/wcs/utils.pytpixel_to_skycoord²s.        ( t __future__RRRRtnumpyR!RdRRZtextern.six.movesRRRRt__doctest_skip__t__all__RR&R)tobjectR'R9R@RGRLRHR^RIRvRR(((s0lib/python2.7/site-packages/astropy/wcs/utils.pyts0"     5  & , = 2   G