/*============================================================================ WCSLIB 7.12 - an implementation of the FITS WCS standard. Copyright (C) 1995-2022, Mark Calabretta This file is part of WCSLIB. WCSLIB is free software: you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. WCSLIB is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with WCSLIB. If not, see http://www.gnu.org/licenses. Author: Mark Calabretta, Australia Telescope National Facility, CSIRO. http://www.atnf.csiro.au/people/Mark.Calabretta $Id: wcs.h,v 7.12 2022/09/09 04:57:58 mcalabre Exp $ *============================================================================= * * WCSLIB 7.12 - C routines that implement the FITS World Coordinate System * (WCS) standard. Refer to the README file provided with WCSLIB for an * overview of the library. * * * Summary of the wcs routines * --------------------------- * Routines in this suite implement the FITS World Coordinate System (WCS) * standard which defines methods to be used for computing world coordinates * from image pixel coordinates, and vice versa. The standard, and proposed * extensions for handling distortions, are described in * = "Representations of world coordinates in FITS", = Greisen, E.W., & Calabretta, M.R. 2002, A&A, 395, 1061 (WCS Paper I) = = "Representations of celestial coordinates in FITS", = Calabretta, M.R., & Greisen, E.W. 2002, A&A, 395, 1077 (WCS Paper II) = = "Representations of spectral coordinates in FITS", = Greisen, E.W., Calabretta, M.R., Valdes, F.G., & Allen, S.L. = 2006, A&A, 446, 747 (WCS Paper III) = = "Representations of distortions in FITS world coordinate systems", = Calabretta, M.R. et al. (WCS Paper IV, draft dated 2004/04/22), = available from http://www.atnf.csiro.au/people/Mark.Calabretta = = "Mapping on the HEALPix grid", = Calabretta, M.R., & Roukema, B.F. 2007, MNRAS, 381, 865 (WCS Paper V) = = "Representing the 'Butterfly' Projection in FITS -- Projection Code XPH", = Calabretta, M.R., & Lowe, S.R. 2013, PASA, 30, e050 (WCS Paper VI) = = "Representations of time coordinates in FITS - = Time and relative dimension in space", = Rots, A.H., Bunclark, P.S., Calabretta, M.R., Allen, S.L., = Manchester, R.N., & Thompson, W.T. 2015, A&A, 574, A36 (WCS Paper VII) * * These routines are based on the wcsprm struct which contains all information * needed for the computations. The struct contains some members that must be * set by the user, and others that are maintained by these routines, somewhat * like a C++ class but with no encapsulation. * * wcsnpv(), wcsnps(), wcsini(), wcsinit(), wcssub(), wcsfree(), and wcstrim(), * are provided to manage the wcsprm struct, wcssize() computes its total size * including allocated memory, and wcsprt() prints its contents. Refer to the * description of the wcsprm struct for an explanation of the anticipated usage * of these routines. wcscopy(), which does a deep copy of one wcsprm struct * to another, is defined as a preprocessor macro function that invokes * wcssub(). * * wcsperr() prints the error message(s) (if any) stored in a wcsprm struct, * and the linprm, celprm, prjprm, spcprm, and tabprm structs that it contains. * * A setup routine, wcsset(), computes intermediate values in the wcsprm struct * from parameters in it that were supplied by the user. The struct always * needs to be set up by wcsset() but this need not be called explicitly - * refer to the explanation of wcsprm::flag. * * wcsp2s() and wcss2p() implement the WCS world coordinate transformations. * In fact, they are high level driver routines for the WCS linear, * logarithmic, celestial, spectral and tabular transformation routines * described in lin.h, log.h, cel.h, spc.h and tab.h. * * Given either the celestial longitude or latitude plus an element of the * pixel coordinate a hybrid routine, wcsmix(), iteratively solves for the * unknown elements. * * wcsccs() changes the celestial coordinate system of a wcsprm struct, for * example, from equatorial to galactic, and wcssptr() translates the spectral * axis. For example, a 'FREQ' axis may be translated into 'ZOPT-F2W' and vice * versa. * * wcslib_version() returns the WCSLIB version number. * * Quadcube projections: * --------------------- * The quadcube projections (TSC, CSC, QSC) may be represented in FITS in * either of two ways: * * a: The six faces may be laid out in one plane and numbered as follows: * = 0 = = 4 3 2 1 4 3 2 = = 5 * * Faces 2, 3 and 4 may appear on one side or the other (or both). The * world-to-pixel routines map faces 2, 3 and 4 to the left but the * pixel-to-world routines accept them on either side. * * b: The "COBE" convention in which the six faces are stored in a * three-dimensional structure using a CUBEFACE axis indexed from * 0 to 5 as above. * * These routines support both methods; wcsset() determines which is being * used by the presence or absence of a CUBEFACE axis in ctype[]. wcsp2s() * and wcss2p() translate the CUBEFACE axis representation to the single * plane representation understood by the lower-level WCSLIB projection * routines. * * * wcsnpv() - Memory allocation for PVi_ma * --------------------------------------- * wcsnpv() sets or gets the value of NPVMAX (default 64). This global * variable controls the number of pvcard structs, for holding PVi_ma * keyvalues, that wcsini() should allocate space for. It is also used by * wcsinit() as the default value of npvmax. * * PLEASE NOTE: This function is not thread-safe. * * Given: * n int Value of NPVMAX; ignored if < 0. Use a value less * than zero to get the current value. * * Function return value: * int Current value of NPVMAX. * * * wcsnps() - Memory allocation for PSi_ma * --------------------------------------- * wcsnps() sets or gets the value of NPSMAX (default 8). This global variable * controls the number of pscard structs, for holding PSi_ma keyvalues, that * wcsini() should allocate space for. It is also used by wcsinit() as the * default value of npsmax. * * PLEASE NOTE: This function is not thread-safe. * * Given: * n int Value of NPSMAX; ignored if < 0. Use a value less * than zero to get the current value. * * Function return value: * int Current value of NPSMAX. * * * wcsini() - Default constructor for the wcsprm struct * ---------------------------------------------------- * wcsini() is a thin wrapper on wcsinit(). It invokes it with npvmax, * npsmax, and ndpmax set to -1 which causes it to use the values of the * global variables NDPMAX, NPSMAX, and NDPMAX. It is thereby potentially * thread-unsafe if these variables are altered dynamically via wcsnpv(), * wcsnps(), and disndp(). Use wcsinit() for a thread-safe alternative in * this case. * * * wcsinit() - Default constructor for the wcsprm struct * ----------------------------------------------------- * wcsinit() optionally allocates memory for arrays in a wcsprm struct and sets * all members of the struct to default values. * * PLEASE NOTE: every wcsprm struct should be initialized by wcsinit(), * possibly repeatedly. On the first invokation, and only the first * invokation, wcsprm::flag must be set to -1 to initialize memory management, * regardless of whether wcsinit() will actually be used to allocate memory. * * Given: * alloc int If true, allocate memory unconditionally for the * crpix, etc. arrays. Please note that memory is never * allocated by wcsinit() for the auxprm, tabprm, nor * wtbarr structs. * * If false, it is assumed that pointers to these arrays * have been set by the user except if they are null * pointers in which case memory will be allocated for * them regardless. (In other words, setting alloc true * saves having to initalize these pointers to zero.) * * naxis int The number of world coordinate axes. This is used to * determine the length of the various wcsprm vectors and * matrices and therefore the amount of memory to * allocate for them. * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Note that, in order to initialize memory management, * wcsprm::flag should be set to -1 when wcs is * initialized for the first time (memory leaks may * result if it had already been initialized). * * Given: * npvmax int The number of PVi_ma keywords to allocate space for. * If set to -1, the value of the global variable NPVMAX * will be used. This is potentially thread-unsafe if * wcsnpv() is being used dynamically to alter its value. * * npsmax int The number of PSi_ma keywords to allocate space for. * If set to -1, the value of the global variable NPSMAX * will be used. This is potentially thread-unsafe if * wcsnps() is being used dynamically to alter its value. * * ndpmax int The number of DPja or DQia keywords to allocate space * for. If set to -1, the value of the global variable * NDPMAX will be used. This is potentially * thread-unsafe if disndp() is being used dynamically to * alter its value. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * * wcsauxi() - Default constructor for the auxprm struct * ----------------------------------------------------- * wcsauxi() optionally allocates memory for an auxprm struct, attaches it to * wcsprm, and sets all members of the struct to default values. * * Given: * alloc int If true, allocate memory unconditionally for the * auxprm struct. * * If false, it is assumed that wcsprm::aux has already * been set to point to an auxprm struct, in which case * the user is responsible for managing that memory. * However, if wcsprm::aux is a null pointer, memory will * be allocated regardless. (In other words, setting * alloc true saves having to initalize the pointer to * zero.) * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * * * wcssub() - Subimage extraction routine for the wcsprm struct * ------------------------------------------------------------ * wcssub() extracts the coordinate description for a subimage from a wcsprm * struct. It does a deep copy, using wcsinit() to allocate memory for its * arrays if required. Only the "information to be provided" part of the * struct is extracted. Consequently, wcsset() need not have been, and won't * be invoked on the struct from which the subimage is extracted. A call to * wcsset() is required to set up the subimage struct. * * The world coordinate system of the subimage must be separable in the sense * that the world coordinates at any point in the subimage must depend only on * the pixel coordinates of the axes extracted. In practice, this means that * the linear transformation matrix of the original image must not contain * non-zero off-diagonal terms that associate any of the subimage axes with any * of the non-subimage axes. Likewise, if any distortions are associated with * the subimage axes, they must not depend on any of the axes that are not * being extracted. * * Note that while the required elements of the tabprm array are extracted, the * wtbarr array is not. (Thus it is not appropriate to call wcssub() after * wcstab() but before filling the tabprm structs - refer to wcshdr.h.) * * wcssub() can also add axes to a wcsprm struct. The new axes will be created * using the defaults set by wcsinit() which produce a simple, unnamed, linear * axis with world coordinate equal to the pixel coordinate. These default * values can be changed afterwards, before invoking wcsset(). * * Given: * alloc int If true, allocate memory for the crpix, etc. arrays in * the destination. Otherwise, it is assumed that * pointers to these arrays have been set by the user * except if they are null pointers in which case memory * will be allocated for them regardless. * * wcssrc const struct wcsprm* * Struct to extract from. * * Given and returned: * nsub int* * axes int[] Vector of length *nsub containing the image axis * numbers (1-relative) to extract. Order is * significant; axes[0] is the axis number of the input * image that corresponds to the first axis in the * subimage, etc. * * Use an axis number of 0 to create a new axis using * the defaults set by wcsinit(). They can be changed * later. * * nsub (the pointer) may be set to zero, and so also may * *nsub, which is interpreted to mean all axes in the * input image; the number of axes will be returned if * nsub != 0x0. axes itself (the pointer) may be set to * zero to indicate the first *nsub axes in their * original order. * * Set both nsub (or *nsub) and axes to zero to do a deep * copy of one wcsprm struct to another. * * Subimage extraction by coordinate axis type may be * done by setting the elements of axes[] to the * following special preprocessor macro values: * * WCSSUB_LONGITUDE: Celestial longitude. * WCSSUB_LATITUDE: Celestial latitude. * WCSSUB_CUBEFACE: Quadcube CUBEFACE axis. * WCSSUB_SPECTRAL: Spectral axis. * WCSSUB_STOKES: Stokes axis. * WCSSUB_TIME: Time axis. * * Refer to the notes (below) for further usage examples. * * On return, *nsub will be set to the number of axes in * the subimage; this may be zero if there were no axes * of the required type(s) (in which case no memory will * be allocated). axes[] will contain the axis numbers * that were extracted, or 0 for newly created axes. The * vector length must be sufficient to contain all axis * numbers. No checks are performed to verify that the * coordinate axes are consistent, this is done by * wcsset(). * * wcsdst struct wcsprm* * Struct describing the subimage. wcsprm::flag should * be set to -1 if wcsdst was not previously initialized * (memory leaks may result if it was previously * initialized). * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * 12: Invalid subimage specification. * 13: Non-separable subimage coordinate system. * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * Notes: * 1: Combinations of subimage axes of particular types may be extracted in * the same order as they occur in the input image by combining * preprocessor codes, for example * = *nsub = 1; = axes[0] = WCSSUB_LONGITUDE | WCSSUB_LATITUDE | WCSSUB_SPECTRAL; * * would extract the longitude, latitude, and spectral axes in the same * order as the input image. If one of each were present, *nsub = 3 would * be returned. * * For convenience, WCSSUB_CELESTIAL is defined as the combination * WCSSUB_LONGITUDE | WCSSUB_LATITUDE | WCSSUB_CUBEFACE. * * The codes may also be negated to extract all but the types specified, * for example * = *nsub = 4; = axes[0] = WCSSUB_LONGITUDE; = axes[1] = WCSSUB_LATITUDE; = axes[2] = WCSSUB_CUBEFACE; = axes[3] = -(WCSSUB_SPECTRAL | WCSSUB_STOKES); * * The last of these specifies all axis types other than spectral or * Stokes. Extraction is done in the order specified by axes[] a * longitude axis (if present) would be extracted first (via axes[0]) and * not subsequently (via axes[3]). Likewise for the latitude and cubeface * axes in this example. * * From the foregoing, it is apparent that the value of *nsub returned may * be less than or greater than that given. However, it will never exceed * the number of axes in the input image (plus the number of newly-created * axes if any were specified on input). * * * wcscompare() - Compare two wcsprm structs for equality * ------------------------------------------------------ * wcscompare() compares two wcsprm structs for equality. * * Given: * cmp int A bit field controlling the strictness of the * comparison. When 0, all fields must be identical. * * The following constants may be or'ed together to * relax the comparison: * WCSCOMPARE_ANCILLARY: Ignore ancillary keywords * that don't change the WCS transformation, such * as DATE-OBS or EQUINOX. * WCSCOMPARE_TILING: Ignore integral differences in * CRPIXja. This is the 'tiling' condition, where * two WCSes cover different regions of the same * map projection and align on the same map grid. * WCSCOMPARE_CRPIX: Ignore any differences at all in * CRPIXja. The two WCSes cover different regions * of the same map projection but may not align on * the same map grid. Overrides WCSCOMPARE_TILING. * * tol double Tolerance for comparison of floating-point values. * For example, for tol == 1e-6, all floating-point * values in the structs must be equal to the first 6 * decimal places. A value of 0 implies exact equality. * * wcs1 const struct wcsprm* * The first wcsprm struct to compare. * * wcs2 const struct wcsprm* * The second wcsprm struct to compare. * * Returned: * equal int* Non-zero when the given structs are equal. * * Function return value: * int Status return value: * 0: Success. * 1: Null pointer passed. * * * wcscopy() macro - Copy routine for the wcsprm struct * ---------------------------------------------------- * wcscopy() does a deep copy of one wcsprm struct to another. As of * WCSLIB 3.6, it is implemented as a preprocessor macro that invokes * wcssub() with the nsub and axes pointers both set to zero. * * * wcsfree() - Destructor for the wcsprm struct * -------------------------------------------- * wcsfree() frees memory allocated for the wcsprm arrays by wcsinit() and/or * wcsset(). wcsinit() records the memory it allocates and wcsfree() will only * attempt to free this. * * PLEASE NOTE: wcsfree() must not be invoked on a wcsprm struct that was not * initialized by wcsinit(). * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * * * wcstrim() - Free unused arrays in the wcsprm struct * --------------------------------------------------- * wcstrim() frees memory allocated by wcsinit() for arrays in the wcsprm * struct that remains unused after it has been set up by wcsset(). * * The free'd array members are associated with FITS WCS keyrecords that are * rarely used and usually just bloat the struct: wcsprm::crota, wcsprm::colax, * wcsprm::cname, wcsprm::crder, wcsprm::csyer, wcsprm::czphs, and * wcsprm::cperi. If unused, wcsprm::pv, wcsprm::ps, and wcsprm::cd are also * freed. * * Once these arrays have been freed, a test such as = = if (!undefined(wcs->cname[i])) {...} = * must be protected as follows = = if (wcs->cname && !undefined(wcs->cname[i])) {...} = * In addition, if wcsprm::npv is non-zero but less than wcsprm::npvmax, then * the unused space in wcsprm::pv will be recovered (using realloc()). * Likewise for wcsprm::ps. * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 14: wcsprm struct is unset. * * * wcssize() - Compute the size of a wcsprm struct * ----------------------------------------------- * wcssize() computes the full size of a wcsprm struct, including allocated * memory. * * Given: * wcs const struct wcsprm* * Coordinate transformation parameters. * * If NULL, the base size of the struct and the allocated * size are both set to zero. * * Returned: * sizes int[2] The first element is the base size of the struct as * returned by sizeof(struct wcsprm). The second element * is the total allocated size, in bytes, assuming that * the allocation was done by wcsini(). This figure * includes memory allocated for members of constituent * structs, such as wcsprm::lin. * * It is not an error for the struct not to have been set * up via wcsset(), which normally results in additional * memory allocation. * * Function return value: * int Status return value: * 0: Success. * * * auxsize() - Compute the size of a auxprm struct * ----------------------------------------------- * auxsize() computes the full size of a auxprm struct, including allocated * memory. * * Given: * aux const struct auxprm* * Auxiliary coordinate information. * * If NULL, the base size of the struct and the allocated * size are both set to zero. * * Returned: * sizes int[2] The first element is the base size of the struct as * returned by sizeof(struct auxprm). The second element * is the total allocated size, in bytes, currently zero. * * Function return value: * int Status return value: * 0: Success. * * * wcsprt() - Print routine for the wcsprm struct * ---------------------------------------------- * wcsprt() prints the contents of a wcsprm struct using wcsprintf(). Mainly * intended for diagnostic purposes. * * Given: * wcs const struct wcsprm* * Coordinate transformation parameters. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * * * wcsperr() - Print error messages from a wcsprm struct * ----------------------------------------------------- * wcsperr() prints the error message(s), if any, stored in a wcsprm struct, * and the linprm, celprm, prjprm, spcprm, and tabprm structs that it contains. * If there are no errors then nothing is printed. It uses wcserr_prt(), q.v. * * Given: * wcs const struct wcsprm* * Coordinate transformation parameters. * * prefix const char * * If non-NULL, each output line will be prefixed with * this string. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * * * wcsbchk() - Enable/disable bounds checking * ------------------------------------------ * wcsbchk() is used to control bounds checking in the projection routines. * Note that wcsset() always enables bounds checking. wcsbchk() will invoke * wcsset() on the wcsprm struct beforehand if necessary. * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Given: * bounds int If bounds&1 then enable strict bounds checking for the * spherical-to-Cartesian (s2x) transformation for the * AZP, SZP, TAN, SIN, ZPN, and COP projections. * * If bounds&2 then enable strict bounds checking for the * Cartesian-to-spherical (x2s) transformation for the * HPX and XPH projections. * * If bounds&4 then enable bounds checking on the native * coordinates returned by the Cartesian-to-spherical * (x2s) transformations using prjchk(). * * Zero it to disable all checking. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * * * wcsset() - Setup routine for the wcsprm struct * ---------------------------------------------- * wcsset() sets up a wcsprm struct according to information supplied within * it (refer to the description of the wcsprm struct). * * wcsset() recognizes the NCP projection and converts it to the equivalent SIN * projection and likewise translates GLS into SFL. It also translates the * AIPS spectral types ('FREQ-LSR', 'FELO-HEL', etc.), possibly changing the * input header keywords wcsprm::ctype and/or wcsprm::specsys if necessary. * * Note that this routine need not be called directly; it will be invoked by * wcsp2s() and wcss2p() if the wcsprm::flag is anything other than a * predefined magic value. * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * 3: Linear transformation matrix is singular. * 4: Inconsistent or unrecognized coordinate axis * types. * 5: Invalid parameter value. * 6: Invalid coordinate transformation parameters. * 7: Ill-conditioned coordinate transformation * parameters. * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * Notes: * 1: wcsset() always enables strict bounds checking in the projection * routines (via a call to prjini()). Use wcsbchk() to modify * bounds-checking after wcsset() is invoked. * * * wcsp2s() - Pixel-to-world transformation * ---------------------------------------- * wcsp2s() transforms pixel coordinates to world coordinates. * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Given: * ncoord, * nelem int The number of coordinates, each of vector length * nelem but containing wcs.naxis coordinate elements. * Thus nelem must equal or exceed the value of the * NAXIS keyword unless ncoord == 1, in which case nelem * is not used. * * pixcrd const double[ncoord][nelem] * Array of pixel coordinates. * * Returned: * imgcrd double[ncoord][nelem] * Array of intermediate world coordinates. For * celestial axes, imgcrd[][wcs.lng] and * imgcrd[][wcs.lat] are the projected x-, and * y-coordinates in pseudo "degrees". For spectral * axes, imgcrd[][wcs.spec] is the intermediate spectral * coordinate, in SI units. * * phi,theta double[ncoord] * Longitude and latitude in the native coordinate system * of the projection [deg]. * * world double[ncoord][nelem] * Array of world coordinates. For celestial axes, * world[][wcs.lng] and world[][wcs.lat] are the * celestial longitude and latitude [deg]. For * spectral axes, imgcrd[][wcs.spec] is the intermediate * spectral coordinate, in SI units. * * stat int[ncoord] * Status return value for each coordinate: * 0: Success. * 1+: A bit mask indicating invalid pixel coordinate * element(s). * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * 3: Linear transformation matrix is singular. * 4: Inconsistent or unrecognized coordinate axis * types. * 5: Invalid parameter value. * 6: Invalid coordinate transformation parameters. * 7: Ill-conditioned coordinate transformation * parameters. * 8: One or more of the pixel coordinates were * invalid, as indicated by the stat vector. * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * * wcss2p() - World-to-pixel transformation * ---------------------------------------- * wcss2p() transforms world coordinates to pixel coordinates. * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * Given: * ncoord, * nelem int The number of coordinates, each of vector length nelem * but containing wcs.naxis coordinate elements. Thus * nelem must equal or exceed the value of the NAXIS * keyword unless ncoord == 1, in which case nelem is not * used. * * world const double[ncoord][nelem] * Array of world coordinates. For celestial axes, * world[][wcs.lng] and world[][wcs.lat] are the * celestial longitude and latitude [deg]. For spectral * axes, world[][wcs.spec] is the spectral coordinate, in * SI units. * * Returned: * phi,theta double[ncoord] * Longitude and latitude in the native coordinate * system of the projection [deg]. * * imgcrd double[ncoord][nelem] * Array of intermediate world coordinates. For * celestial axes, imgcrd[][wcs.lng] and * imgcrd[][wcs.lat] are the projected x-, and * y-coordinates in pseudo "degrees". For quadcube * projections with a CUBEFACE axis the face number is * also returned in imgcrd[][wcs.cubeface]. For * spectral axes, imgcrd[][wcs.spec] is the intermediate * spectral coordinate, in SI units. * * pixcrd double[ncoord][nelem] * Array of pixel coordinates. * * stat int[ncoord] * Status return value for each coordinate: * 0: Success. * 1+: A bit mask indicating invalid world coordinate * element(s). * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * 3: Linear transformation matrix is singular. * 4: Inconsistent or unrecognized coordinate axis * types. * 5: Invalid parameter value. * 6: Invalid coordinate transformation parameters. * 7: Ill-conditioned coordinate transformation * parameters. * 9: One or more of the world coordinates were * invalid, as indicated by the stat vector. * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * * wcsmix() - Hybrid coordinate transformation * ------------------------------------------- * wcsmix(), given either the celestial longitude or latitude plus an element * of the pixel coordinate, solves for the remaining elements by iterating on * the unknown celestial coordinate element using wcss2p(). Refer also to the * notes below. * * Given and returned: * wcs struct wcsprm* * Indices for the celestial coordinates obtained * by parsing the wcsprm::ctype[]. * * Given: * mixpix int Which element of the pixel coordinate is given. * * mixcel int Which element of the celestial coordinate is given: * 1: Celestial longitude is given in * world[wcs.lng], latitude returned in * world[wcs.lat]. * 2: Celestial latitude is given in * world[wcs.lat], longitude returned in * world[wcs.lng]. * * vspan const double[2] * Solution interval for the celestial coordinate [deg]. * The ordering of the two limits is irrelevant. * Longitude ranges may be specified with any convenient * normalization, for example [-120,+120] is the same as * [240,480], except that the solution will be returned * with the same normalization, i.e. lie within the * interval specified. * * vstep const double * Step size for solution search [deg]. If zero, a * sensible, although perhaps non-optimal default will be * used. * * viter int If a solution is not found then the step size will be * halved and the search recommenced. viter controls how * many times the step size is halved. The allowed range * is 5 - 10. * * Given and returned: * world double[naxis] * World coordinate elements. world[wcs.lng] and * world[wcs.lat] are the celestial longitude and * latitude [deg]. Which is given and which returned * depends on the value of mixcel. All other elements * are given. * * Returned: * phi,theta double[naxis] * Longitude and latitude in the native coordinate * system of the projection [deg]. * * imgcrd double[naxis] * Image coordinate elements. imgcrd[wcs.lng] and * imgcrd[wcs.lat] are the projected x-, and * y-coordinates in pseudo "degrees". * * Given and returned: * pixcrd double[naxis] * Pixel coordinate. The element indicated by mixpix is * given and the remaining elements are returned. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * 3: Linear transformation matrix is singular. * 4: Inconsistent or unrecognized coordinate axis * types. * 5: Invalid parameter value. * 6: Invalid coordinate transformation parameters. * 7: Ill-conditioned coordinate transformation * parameters. * 10: Invalid world coordinate. * 11: No solution found in the specified interval. * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * Notes: * 1: Initially the specified solution interval is checked to see if it's a * "crossing" interval. If it isn't, a search is made for a crossing * solution by iterating on the unknown celestial coordinate starting at * the upper limit of the solution interval and decrementing by the * specified step size. A crossing is indicated if the trial value of the * pixel coordinate steps through the value specified. If a crossing * interval is found then the solution is determined by a modified form of * "regula falsi" division of the crossing interval. If no crossing * interval was found within the specified solution interval then a search * is made for a "non-crossing" solution as may arise from a point of * tangency. The process is complicated by having to make allowance for * the discontinuities that occur in all map projections. * * Once one solution has been determined others may be found by subsequent * invokations of wcsmix() with suitably restricted solution intervals. * * Note the circumstance that arises when the solution point lies at a * native pole of a projection in which the pole is represented as a * finite curve, for example the zenithals and conics. In such cases two * or more valid solutions may exist but wcsmix() only ever returns one. * * Because of its generality wcsmix() is very compute-intensive. For * compute-limited applications more efficient special-case solvers could * be written for simple projections, for example non-oblique cylindrical * projections. * * * wcsccs() - Change celestial coordinate system * --------------------------------------------- * wcsccs() changes the celestial coordinate system of a wcsprm struct. For * example, from equatorial to galactic coordinates. * * Parameters that define the spherical coordinate transformation, essentially * being three Euler angles, must be provided. Thereby wcsccs() does not need * prior knowledge of specific celestial coordinate systems. It also has the * advantage of making it completely general. * * Auxiliary members of the wcsprm struct relating to equatorial celestial * coordinate systems may also be changed. * * Only orthodox spherical coordinate systems are supported. That is, they * must be right-handed, with latitude increasing from zero at the equator to * +90 degrees at the pole. This precludes systems such as aziumuth and zenith * distance, which, however, could be handled as negative azimuth and * elevation. * * PLEASE NOTE: Information in the wcsprm struct relating to the original * coordinate system will be overwritten and therefore lost. If this is * undesirable, invoke wcsccs() on a copy of the struct made with wcssub(). * The wcsprm struct is reset on return with an explicit call to wcsset(). * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. Particular * "values to be given" elements of the wcsprm struct * are modified. * * Given: * lng2p1, * lat2p1 double Longitude and latitude in the new celestial coordinate * system of the pole (i.e. latitude +90) of the original * system [deg]. See notes 1 and 2 below. * * lng1p2 double Longitude in the original celestial coordinate system * of the pole (i.e. latitude +90) of the new system * [deg]. See note 1 below. * * clng,clat const char* * Longitude and latitude identifiers of the new CTYPEia * celestial axis codes, without trailing dashes. For * example, "RA" and "DEC" or "GLON" and "GLAT". Up to * four characters are used, longer strings need not be * null-terminated. * * radesys const char* * Used when transforming to equatorial coordinates, * identified by clng == "RA" and clat = "DEC". May be * set to the null pointer to preserve the current value. * Up to 71 characters are used, longer strings need not * be null-terminated. * * If the new coordinate system is anything other than * equatorial, then wcsprm::radesys will be cleared. * * equinox double Used when transforming to equatorial coordinates. May * be set to zero to preserve the current value. * * If the new coordinate system is not equatorial, then * wcsprm::equinox will be marked as undefined. * * alt const char* * Character code for alternate coordinate descriptions * (i.e. the 'a' in keyword names such as CTYPEia). This * is blank for the primary coordinate description, or * one of the 26 upper-case letters, A-Z. May be set to * the null pointer, or null string if no change is * required. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 12: Invalid subimage specification (no celestial * axes). * * Notes: * 1: Follows the prescription given in WCS Paper II, Sect. 2.7 for changing * celestial coordinates. * * The implementation takes account of indeterminacies that arise in that * prescription in the particular cases where one of the poles of the new * system is at the fiducial point, or one of them is at the native pole. * * 2: If lat2p1 == +90, i.e. where the poles of the two coordinate systems * coincide, then the spherical coordinate transformation becomes a simple * change in origin of longitude given by * lng2 = lng1 + (lng2p1 - lng1p2 - 180), and lat2 = lat1, where * (lng2,lat2) are coordinates in the new system, and (lng1,lat1) are * coordinates in the original system. * * Likewise, if lat2p1 == -90, then lng2 = -lng1 + (lng2p1 + lng1p2), and * lat2 = -lat1. * * 3: For example, if the original coordinate system is B1950 equatorial and * the desired new coordinate system is galactic, then * * - (lng2p1,lat2p1) are the galactic coordinates of the B1950 celestial * pole, defined by the IAU to be (123.0,+27.4), and lng1p2 is the B1950 * right ascension of the galactic pole, defined as 192.25. Clearly * these coordinates are fixed for a particular coordinate * transformation. * * - (clng,clat) would be 'GLON' and 'GLAT', these being the FITS standard * identifiers for galactic coordinates. * * - Since the new coordinate system is not equatorial, wcsprm::radesys * and wcsprm::equinox will be cleared. * * 4. The coordinates required for some common transformations (obtained from * https://ned.ipac.caltech.edu/coordinate_calculator) are as follows: * = (123.0000,+27.4000) galactic coordinates of B1950 celestial pole, = (192.2500,+27.4000) B1950 equatorial coordinates of galactic pole. * = (122.9319,+27.1283) galactic coordinates of J2000 celestial pole, = (192.8595,+27.1283) J2000 equatorial coordinates of galactic pole. * = (359.6774,+89.7217) B1950 equatorial coordinates of J2000 pole, = (180.3162,+89.7217) J2000 equatorial coordinates of B1950 pole. * = (270.0000,+66.5542) B1950 equatorial coordinates of B1950 ecliptic pole, = ( 90.0000,+66.5542) B1950 ecliptic coordinates of B1950 celestial pole. * = (270.0000,+66.5607) J2000 equatorial coordinates of J2000 ecliptic pole, = ( 90.0000,+66.5607) J2000 ecliptic coordinates of J2000 celestial pole. * = ( 26.7315,+15.6441) supergalactic coordinates of B1950 celestial pole, = (283.1894,+15.6441) B1950 equatorial coordinates of supergalactic pole. * = ( 26.4505,+15.7089) supergalactic coordinates of J2000 celestial pole, = (283.7542,+15.7089) J2000 equatorial coordinates of supergalactic pole. * * * wcssptr() - Spectral axis translation * ------------------------------------- * wcssptr() translates the spectral axis in a wcsprm struct. For example, a * 'FREQ' axis may be translated into 'ZOPT-F2W' and vice versa. * * PLEASE NOTE: Information in the wcsprm struct relating to the original * coordinate system will be overwritten and therefore lost. If this is * undesirable, invoke wcssptr() on a copy of the struct made with wcssub(). * The wcsprm struct is reset on return with an explicit call to wcsset(). * * Given and returned: * wcs struct wcsprm* * Coordinate transformation parameters. * * i int* Index of the spectral axis (0-relative). If given < 0 * it will be set to the first spectral axis identified * from the ctype[] keyvalues in the wcsprm struct. * * ctype char[9] Desired spectral CTYPEia. Wildcarding may be used as * for the ctypeS2 argument to spctrn() as described in * the prologue of spc.h, i.e. if the final three * characters are specified as "???", or if just the * eighth character is specified as '?', the correct * algorithm code will be substituted and returned. * * Function return value: * int Status return value: * 0: Success. * 1: Null wcsprm pointer passed. * 2: Memory allocation failed. * 3: Linear transformation matrix is singular. * 4: Inconsistent or unrecognized coordinate axis * types. * 5: Invalid parameter value. * 6: Invalid coordinate transformation parameters. * 7: Ill-conditioned coordinate transformation * parameters. * 12: Invalid subimage specification (no spectral * axis). * * For returns > 1, a detailed error message is set in * wcsprm::err if enabled, see wcserr_enable(). * * * wcslib_version() - WCSLIB version number * ---------------------------------------- * wcslib_version() returns the WCSLIB version number. * * The major version number changes when the ABI changes or when the license * conditions change. ABI changes typically result from a change to the * contents of one of the structs. The major version number is used to * distinguish between incompatible versions of the sharable library. * * The minor version number changes with new functionality or bug fixes that do * not involve a change in the ABI. * * The auxiliary version number (which is often absent) signals changes to the * documentation, test suite, build procedures, or any other change that does * not affect the compiled library. * * Returned: * vers[3] int[3] The broken-down version number: * 0: Major version number. * 1: Minor version number. * 2: Auxiliary version number (zero if absent). * May be given as a null pointer if not required. * * Function return value: * char* A null-terminated, statically allocated string * containing the version number in the usual form, i.e. * "..". * * * wcsprm struct - Coordinate transformation parameters * ---------------------------------------------------- * The wcsprm struct contains information required to transform world * coordinates. It consists of certain members that must be set by the user * ("given") and others that are set by the WCSLIB routines ("returned"). * While the addresses of the arrays themselves may be set by wcsinit() if it * (optionally) allocates memory, their contents must be set by the user. * * Some parameters that are given are not actually required for transforming * coordinates. These are described as "auxiliary"; the struct simply provides * a place to store them, though they may be used by wcshdo() in constructing a * FITS header from a wcsprm struct. Some of the returned values are supplied * for informational purposes and others are for internal use only as * indicated. * * In practice, it is expected that a WCS parser would scan the FITS header to * determine the number of coordinate axes. It would then use wcsinit() to * allocate memory for arrays in the wcsprm struct and set default values. * Then as it reread the header and identified each WCS keyrecord it would load * the value into the relevant wcsprm array element. This is essentially what * wcspih() does - refer to the prologue of wcshdr.h. As the final step, * wcsset() is invoked, either directly or indirectly, to set the derived * members of the wcsprm struct. wcsset() strips off trailing blanks in all * string members and null-fills the character array. * * int flag * (Given and returned) This flag must be set to zero whenever any of the * following wcsprm struct members are set or changed: * * - wcsprm::naxis (q.v., not normally set by the user), * - wcsprm::crpix, * - wcsprm::pc, * - wcsprm::cdelt, * - wcsprm::crval, * - wcsprm::cunit, * - wcsprm::ctype, * - wcsprm::lonpole, * - wcsprm::latpole, * - wcsprm::restfrq, * - wcsprm::restwav, * - wcsprm::npv, * - wcsprm::pv, * - wcsprm::nps, * - wcsprm::ps, * - wcsprm::cd, * - wcsprm::crota, * - wcsprm::altlin, * - wcsprm::ntab, * - wcsprm::nwtb, * - wcsprm::tab, * - wcsprm::wtb. * * This signals the initialization routine, wcsset(), to recompute the * returned members of the linprm, celprm, spcprm, and tabprm structs. * wcsset() will reset flag to indicate that this has been done. * * PLEASE NOTE: flag should be set to -1 when wcsinit() is called for the * first time for a particular wcsprm struct in order to initialize memory * management. It must ONLY be used on the first initialization otherwise * memory leaks may result. * * int naxis * (Given or returned) Number of pixel and world coordinate elements. * * If wcsinit() is used to initialize the linprm struct (as would normally * be the case) then it will set naxis from the value passed to it as a * function argument. The user should not subsequently modify it. * * double *crpix * (Given) Address of the first element of an array of double containing * the coordinate reference pixel, CRPIXja. * * double *pc * (Given) Address of the first element of the PCi_ja (pixel coordinate) * transformation matrix. The expected order is * = struct wcsprm wcs; = wcs.pc = {PC1_1, PC1_2, PC2_1, PC2_2}; * * This may be constructed conveniently from a 2-D array via * = double m[2][2] = {{PC1_1, PC1_2}, = {PC2_1, PC2_2}}; * * which is equivalent to * = double m[2][2]; = m[0][0] = PC1_1; = m[0][1] = PC1_2; = m[1][0] = PC2_1; = m[1][1] = PC2_2; * * The storage order for this 2-D array is the same as for the 1-D array, * whence * = wcs.pc = *m; * * would be legitimate. * * double *cdelt * (Given) Address of the first element of an array of double containing * the coordinate increments, CDELTia. * * double *crval * (Given) Address of the first element of an array of double containing * the coordinate reference values, CRVALia. * * char (*cunit)[72] * (Given) Address of the first element of an array of char[72] containing * the CUNITia keyvalues which define the units of measurement of the * CRVALia, CDELTia, and CDi_ja keywords. * * As CUNITia is an optional header keyword, cunit[][72] may be left blank * but otherwise is expected to contain a standard units specification as * defined by WCS Paper I. Utility function wcsutrn(), described in * wcsunits.h, is available to translate commonly used non-standard units * specifications but this must be done as a separate step before invoking * wcsset(). * * For celestial axes, if cunit[][72] is not blank, wcsset() uses * wcsunits() to parse it and scale cdelt[], crval[], and cd[][*] to * degrees. It then resets cunit[][72] to "deg". * * For spectral axes, if cunit[][72] is not blank, wcsset() uses wcsunits() * to parse it and scale cdelt[], crval[], and cd[][*] to SI units. It * then resets cunit[][72] accordingly. * * wcsset() ignores cunit[][72] for other coordinate types; cunit[][72] may * be used to label coordinate values. * * These variables accomodate the longest allowed string-valued FITS * keyword, being limited to 68 characters, plus the null-terminating * character. * * char (*ctype)[72] * (Given) Address of the first element of an array of char[72] containing * the coordinate axis types, CTYPEia. * * The ctype[][72] keyword values must be in upper case and there must be * zero or one pair of matched celestial axis types, and zero or one * spectral axis. The ctype[][72] strings should be padded with blanks on * the right and null-terminated so that they are at least eight characters * in length. * * These variables accomodate the longest allowed string-valued FITS * keyword, being limited to 68 characters, plus the null-terminating * character. * * double lonpole * (Given and returned) The native longitude of the celestial pole, phi_p, * given by LONPOLEa [deg] or by PVi_2a [deg] attached to the longitude * axis which takes precedence if defined, and ... * double latpole * (Given and returned) ... the native latitude of the celestial pole, * theta_p, given by LATPOLEa [deg] or by PVi_3a [deg] attached to the * longitude axis which takes precedence if defined. * * lonpole and latpole may be left to default to values set by wcsinit() * (see celprm::ref), but in any case they will be reset by wcsset() to * the values actually used. Note therefore that if the wcsprm struct is * reused without resetting them, whether directly or via wcsinit(), they * will no longer have their default values. * * double restfrq * (Given) The rest frequency [Hz], and/or ... * double restwav * (Given) ... the rest wavelength in vacuo [m], only one of which need be * given, the other should be set to zero. * * int npv * (Given) The number of entries in the wcsprm::pv[] array. * * int npvmax * (Given or returned) The length of the wcsprm::pv[] array. * * npvmax will be set by wcsinit() if it allocates memory for wcsprm::pv[], * otherwise it must be set by the user. See also wcsnpv(). * * struct pvcard *pv * (Given) Address of the first element of an array of length npvmax of * pvcard structs. * * As a FITS header parser encounters each PVi_ma keyword it should load it * into a pvcard struct in the array and increment npv. wcsset() * interprets these as required. * * Note that, if they were not given, wcsset() resets the entries for * PVi_1a, PVi_2a, PVi_3a, and PVi_4a for longitude axis i to match * phi_0 and theta_0 (the native longitude and latitude of the reference * point), LONPOLEa and LATPOLEa respectively. * * int nps * (Given) The number of entries in the wcsprm::ps[] array. * * int npsmax * (Given or returned) The length of the wcsprm::ps[] array. * * npsmax will be set by wcsinit() if it allocates memory for wcsprm::ps[], * otherwise it must be set by the user. See also wcsnps(). * * struct pscard *ps * (Given) Address of the first element of an array of length npsmax of * pscard structs. * * As a FITS header parser encounters each PSi_ma keyword it should load it * into a pscard struct in the array and increment nps. wcsset() * interprets these as required (currently no PSi_ma keyvalues are * recognized). * * double *cd * (Given) For historical compatibility, the wcsprm struct supports two * alternate specifications of the linear transformation matrix, those * associated with the CDi_ja keywords, and ... * double *crota * (Given) ... those associated with the CROTAi keywords. Although these * may not formally co-exist with PCi_ja, the approach taken here is simply * to ignore them if given in conjunction with PCi_ja. * * int altlin * (Given) altlin is a bit flag that denotes which of the PCi_ja, CDi_ja * and CROTAi keywords are present in the header: * * - Bit 0: PCi_ja is present. * * - Bit 1: CDi_ja is present. * * Matrix elements in the IRAF convention are equivalent to the product * CDi_ja = CDELTia * PCi_ja, but the defaults differ from that of the * PCi_ja matrix. If one or more CDi_ja keywords are present then all * unspecified CDi_ja default to zero. If no CDi_ja (or CROTAi) keywords * are present, then the header is assumed to be in PCi_ja form whether * or not any PCi_ja keywords are present since this results in an * interpretation of CDELTia consistent with the original FITS * specification. * * While CDi_ja may not formally co-exist with PCi_ja, it may co-exist * with CDELTia and CROTAi which are to be ignored. * * - Bit 2: CROTAi is present. * * In the AIPS convention, CROTAi may only be associated with the * latitude axis of a celestial axis pair. It specifies a rotation in * the image plane that is applied AFTER the CDELTia; any other CROTAi * keywords are ignored. * * CROTAi may not formally co-exist with PCi_ja. * * CROTAi and CDELTia may formally co-exist with CDi_ja but if so are to * be ignored. * * - Bit 3: PCi_ja + CDELTia was derived from CDi_ja by wcspcx(). * * This bit is set by wcspcx() when it derives PCi_ja and CDELTia from * CDi_ja via an orthonormal decomposition. In particular, it signals * wcsset() not to replace PCi_ja by a copy of CDi_ja with CDELTia set * to unity. * * CDi_ja and CROTAi keywords, if found, are to be stored in the wcsprm::cd * and wcsprm::crota arrays which are dimensioned similarly to wcsprm::pc * and wcsprm::cdelt. FITS header parsers should use the following * procedure: * * - Whenever a PCi_ja keyword is encountered: altlin |= 1; * * - Whenever a CDi_ja keyword is encountered: altlin |= 2; * * - Whenever a CROTAi keyword is encountered: altlin |= 4; * * If none of these bits are set the PCi_ja representation results, i.e. * wcsprm::pc and wcsprm::cdelt will be used as given. * * These alternate specifications of the linear transformation matrix are * translated immediately to PCi_ja by wcsset() and are invisible to the * lower-level WCSLIB routines. In particular, unless bit 3 is also set, * wcsset() resets wcsprm::cdelt to unity if CDi_ja is present (and no * PCi_ja). * * If CROTAi are present but none is associated with the latitude axis * (and no PCi_ja or CDi_ja), then wcsset() reverts to a unity PCi_ja * matrix. * * int velref * (Given) AIPS velocity code VELREF, refer to spcaips(). * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::velref is changed. * * char alt[4] * (Given, auxiliary) Character code for alternate coordinate descriptions * (i.e. the 'a' in keyword names such as CTYPEia). This is blank for the * primary coordinate description, or one of the 26 upper-case letters, * A-Z. * * An array of four characters is provided for alignment purposes, only the * first is used. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::alt is changed. * * int colnum * (Given, auxiliary) Where the coordinate representation is associated * with an image-array column in a FITS binary table, this variable may be * used to record the relevant column number. * * It should be set to zero for an image header or pixel list. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::colnum is changed. * * int *colax * (Given, auxiliary) Address of the first element of an array of int * recording the column numbers for each axis in a pixel list. * * The array elements should be set to zero for an image header or image * array in a binary table. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::colax is changed. * * char (*cname)[72] * (Given, auxiliary) The address of the first element of an array of * char[72] containing the coordinate axis names, CNAMEia. * * These variables accomodate the longest allowed string-valued FITS * keyword, being limited to 68 characters, plus the null-terminating * character. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::cname is changed. * * double *crder * (Given, auxiliary) Address of the first element of an array of double * recording the random error in the coordinate value, CRDERia. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::crder is changed. * * double *csyer * (Given, auxiliary) Address of the first element of an array of double * recording the systematic error in the coordinate value, CSYERia. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::csyer is changed. * * double *czphs * (Given, auxiliary) Address of the first element of an array of double * recording the time at the zero point of a phase axis, CZPHSia. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::czphs is changed. * * double *cperi * (Given, auxiliary) Address of the first element of an array of double * recording the period of a phase axis, CPERIia. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::cperi is changed. * * char wcsname[72] * (Given, auxiliary) The name given to the coordinate representation, * WCSNAMEa. This variable accomodates the longest allowed string-valued * FITS keyword, being limited to 68 characters, plus the null-terminating * character. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::wcsname is changed. * * char timesys[72] * (Given, auxiliary) TIMESYS keyvalue, being the time scale (UTC, TAI, * etc.) in which all other time-related auxiliary header values are * recorded. Also defines the time scale for an image axis with CTYPEia * set to 'TIME'. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timesys is changed. * * char trefpos[72] * (Given, auxiliary) TREFPOS keyvalue, being the location in space where * the recorded time is valid. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::trefpos is changed. * * char trefdir[72] * (Given, auxiliary) TREFDIR keyvalue, being the reference direction used * in calculating a pathlength delay. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::trefdir is changed. * * char plephem[72] * (Given, auxiliary) PLEPHEM keyvalue, being the Solar System ephemeris * used for calculating a pathlength delay. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::plephem is changed. * * char timeunit[72] * (Given, auxiliary) TIMEUNIT keyvalue, being the time units in which * the following header values are expressed: TSTART, TSTOP, TIMEOFFS, * TIMSYER, TIMRDER, TIMEDEL. It also provides the default value for * CUNITia for time axes. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timeunit is changed. * * char dateref[72] * (Given, auxiliary) DATEREF keyvalue, being the date of a reference epoch * relative to which other time measurements refer. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::dateref is changed. * * double mjdref[2] * (Given, auxiliary) MJDREF keyvalue, equivalent to DATEREF expressed as * a Modified Julian Date (MJD = JD - 2400000.5). The value is given as * the sum of the two-element vector, allowing increased precision. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::mjdref is changed. * * double timeoffs * (Given, auxiliary) TIMEOFFS keyvalue, being a time offset, which may be * used, for example, to provide a uniform clock correction for times * referenced to DATEREF. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timeoffs is changed. * * char dateobs[72] * (Given, auxiliary) DATE-OBS keyvalue, being the date at the start of the * observation unless otherwise explained in the DATE-OBS keycomment, in * ISO format, yyyy-mm-ddThh:mm:ss. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::dateobs is changed. * * char datebeg[72] * (Given, auxiliary) DATE-BEG keyvalue, being the date at the start of the * observation in ISO format, yyyy-mm-ddThh:mm:ss. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::datebeg is changed. * * char dateavg[72] * (Given, auxiliary) DATE-AVG keyvalue, being the date at a representative * mid-point of the observation in ISO format, yyyy-mm-ddThh:mm:ss. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::dateavg is changed. * * char dateend[72] * (Given, auxiliary) DATE-END keyvalue, baing the date at the end of the * observation in ISO format, yyyy-mm-ddThh:mm:ss. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::dateend is changed. * * double mjdobs * (Given, auxiliary) MJD-OBS keyvalue, equivalent to DATE-OBS expressed * as a Modified Julian Date (MJD = JD - 2400000.5). * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::mjdobs is changed. * * double mjdbeg * (Given, auxiliary) MJD-BEG keyvalue, equivalent to DATE-BEG expressed * as a Modified Julian Date (MJD = JD - 2400000.5). * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::mjdbeg is changed. * * double mjdavg * (Given, auxiliary) MJD-AVG keyvalue, equivalent to DATE-AVG expressed * as a Modified Julian Date (MJD = JD - 2400000.5). * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::mjdavg is changed. * * double mjdend * (Given, auxiliary) MJD-END keyvalue, equivalent to DATE-END expressed * as a Modified Julian Date (MJD = JD - 2400000.5). * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::mjdend is changed. * * double jepoch * (Given, auxiliary) JEPOCH keyvalue, equivalent to DATE-OBS expressed * as a Julian epoch. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::jepoch is changed. * * double bepoch * (Given, auxiliary) BEPOCH keyvalue, equivalent to DATE-OBS expressed * as a Besselian epoch * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::bepoch is changed. * * double tstart * (Given, auxiliary) TSTART keyvalue, equivalent to DATE-BEG expressed * as a time in units of TIMEUNIT relative to DATEREF+TIMEOFFS. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::tstart is changed. * * double tstop * (Given, auxiliary) TSTOP keyvalue, equivalent to DATE-END expressed * as a time in units of TIMEUNIT relative to DATEREF+TIMEOFFS. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::tstop is changed. * * double xposure * (Given, auxiliary) XPOSURE keyvalue, being the effective exposure time * in units of TIMEUNIT. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::xposure is changed. * * double telapse * (Given, auxiliary) TELAPSE keyvalue, equivalent to the elapsed time * between DATE-BEG and DATE-END, in units of TIMEUNIT. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::telapse is changed. * * double timsyer * (Given, auxiliary) TIMSYER keyvalue, being the absolute error of the * time values, in units of TIMEUNIT. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timsyer is changed. * * double timrder * (Given, auxiliary) TIMRDER keyvalue, being the accuracy of time stamps * relative to each other, in units of TIMEUNIT. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timrder is changed. * * double timedel * (Given, auxiliary) TIMEDEL keyvalue, being the resolution of the time * stamps. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timedel is changed. * * double timepixr * (Given, auxiliary) TIMEPIXR keyvalue, being the relative position of the * time stamps in binned time intervals, a value between 0.0 and 1.0. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::timepixr is changed. * * double obsgeo[6] * (Given, auxiliary) Location of the observer in a standard terrestrial * reference frame. The first three give ITRS Cartesian coordinates * OBSGEO-X [m], OBSGEO-Y [m], OBSGEO-Z [m], and the second three give * OBSGEO-L [deg], OBSGEO-B [deg], OBSGEO-H [m], which are related through * a standard transformation. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::obsgeo is changed. * * char obsorbit[72] * (Given, auxiliary) OBSORBIT keyvalue, being the URI, URL, or name of an * orbit ephemeris file giving spacecraft coordinates relating to TREFPOS. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::obsorbit is changed. * * char radesys[72] * (Given, auxiliary) The equatorial or ecliptic coordinate system type, * RADESYSa. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::radesys is changed. * * double equinox * (Given, auxiliary) The equinox associated with dynamical equatorial or * ecliptic coordinate systems, EQUINOXa (or EPOCH in older headers). Not * applicable to ICRS equatorial or ecliptic coordinates. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::equinox is changed. * * char specsys[72] * (Given, auxiliary) Spectral reference frame (standard of rest), * SPECSYSa. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::specsys is changed. * * char ssysobs[72] * (Given, auxiliary) The spectral reference frame in which there is no * differential variation in the spectral coordinate across the * field-of-view, SSYSOBSa. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::ssysobs is changed. * * double velosys * (Given, auxiliary) The relative radial velocity [m/s] between the * observer and the selected standard of rest in the direction of the * celestial reference coordinate, VELOSYSa. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::velosys is changed. * * double zsource * (Given, auxiliary) The redshift, ZSOURCEa, of the source. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::zsource is changed. * * char ssyssrc[72] * (Given, auxiliary) The spectral reference frame (standard of rest), * SSYSSRCa, in which wcsprm::zsource was measured. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::ssyssrc is changed. * * double velangl * (Given, auxiliary) The angle [deg] that should be used to decompose an * observed velocity into radial and transverse components. * * It is not necessary to reset the wcsprm struct (via wcsset()) when * wcsprm::velangl is changed. * * struct auxprm *aux * (Given, auxiliary) This struct holds auxiliary coordinate system * information of a specialist nature. While these parameters may be * widely recognized within particular fields of astronomy, they differ * from the above auxiliary parameters in not being defined by any of the * FITS WCS standards. Collecting them together in a separate struct that * is allocated only when required helps to control bloat in the size of * the wcsprm struct. * * int ntab * (Given) See wcsprm::tab. * * int nwtb * (Given) See wcsprm::wtb. * * struct tabprm *tab * (Given) Address of the first element of an array of ntab tabprm structs * for which memory has been allocated. These are used to store tabular * transformation parameters. * * Although technically wcsprm::ntab and tab are "given", they will * normally be set by invoking wcstab(), whether directly or indirectly. * * The tabprm structs contain some members that must be supplied and others * that are derived. The information to be supplied comes primarily from * arrays stored in one or more FITS binary table extensions. These * arrays, referred to here as "wcstab arrays", are themselves located by * parameters stored in the FITS image header. * * struct wtbarr *wtb * (Given) Address of the first element of an array of nwtb wtbarr structs * for which memory has been allocated. These are used in extracting * wcstab arrays from a FITS binary table. * * Although technically wcsprm::nwtb and wtb are "given", they will * normally be set by invoking wcstab(), whether directly or indirectly. * * char lngtyp[8] * (Returned) Four-character WCS celestial longitude and ... * char lattyp[8] * (Returned) ... latitude axis types. e.g. "RA", "DEC", "GLON", "GLAT", * etc. extracted from 'RA--', 'DEC-', 'GLON', 'GLAT', etc. in the first * four characters of CTYPEia but with trailing dashes removed. (Declared * as char[8] for alignment reasons.) * * int lng * (Returned) Index for the longitude coordinate, and ... * int lat * (Returned) ... index for the latitude coordinate, and ... * int spec * (Returned) ... index for the spectral coordinate in the imgcrd[][] and * world[][] arrays in the API of wcsp2s(), wcss2p() and wcsmix(). * * These may also serve as indices into the pixcrd[][] array provided that * the PCi_ja matrix does not transpose axes. * * int cubeface * (Returned) Index into the pixcrd[][] array for the CUBEFACE axis. This * is used for quadcube projections where the cube faces are stored on a * separate axis (see wcs.h). * * int *types * (Returned) Address of the first element of an array of int containing a * four-digit type code for each axis. * * - First digit (i.e. 1000s): * - 0: Non-specific coordinate type. * - 1: Stokes coordinate. * - 2: Celestial coordinate (including CUBEFACE). * - 3: Spectral coordinate. * - 4: Time coordinate. * * - Second digit (i.e. 100s): * - 0: Linear axis. * - 1: Quantized axis (STOKES, CUBEFACE). * - 2: Non-linear celestial axis. * - 3: Non-linear spectral axis. * - 4: Logarithmic axis. * - 5: Tabular axis. * * - Third digit (i.e. 10s): * - 0: Group number, e.g. lookup table number, being an index into the * tabprm array (see above). * * - The fourth digit is used as a qualifier depending on the axis type. * * - For celestial axes: * - 0: Longitude coordinate. * - 1: Latitude coordinate. * - 2: CUBEFACE number. * * - For lookup tables: the axis number in a multidimensional table. * * CTYPEia in "4-3" form with unrecognized algorithm code will have its * type set to -1 and generate an error. * * struct linprm lin * (Returned) Linear transformation parameters (usage is described in the * prologue to lin.h). * * struct celprm cel * (Returned) Celestial transformation parameters (usage is described in * the prologue to cel.h). * * struct spcprm spc * (Returned) Spectral transformation parameters (usage is described in the * prologue to spc.h). * * struct wcserr *err * (Returned) If enabled, when an error status is returned, this struct * contains detailed information about the error, see wcserr_enable(). * * int m_flag * (For internal use only.) * int m_naxis * (For internal use only.) * double *m_crpix * (For internal use only.) * double *m_pc * (For internal use only.) * double *m_cdelt * (For internal use only.) * double *m_crval * (For internal use only.) * char (*m_cunit)[72] * (For internal use only.) * char (*m_ctype)[72] * (For internal use only.) * struct pvcard *m_pv * (For internal use only.) * struct pscard *m_ps * (For internal use only.) * double *m_cd * (For internal use only.) * double *m_crota * (For internal use only.) * int *m_colax * (For internal use only.) * char (*m_cname)[72] * (For internal use only.) * double *m_crder * (For internal use only.) * double *m_csyer * (For internal use only.) * double *m_czphs * (For internal use only.) * double *m_cperi * (For internal use only.) * struct tabprm *m_tab * (For internal use only.) * struct wtbarr *m_wtb * (For internal use only.) * * * pvcard struct - Store for PVi_ma keyrecords * ------------------------------------------- * The pvcard struct is used to pass the parsed contents of PVi_ma keyrecords * to wcsset() via the wcsprm struct. * * All members of this struct are to be set by the user. * * int i * (Given) Axis number (1-relative), as in the FITS PVi_ma keyword. If * i == 0, wcsset() will replace it with the latitude axis number. * * int m * (Given) Parameter number (non-negative), as in the FITS PVi_ma keyword. * * double value * (Given) Parameter value. * * * pscard struct - Store for PSi_ma keyrecords * ------------------------------------------- * The pscard struct is used to pass the parsed contents of PSi_ma keyrecords * to wcsset() via the wcsprm struct. * * All members of this struct are to be set by the user. * * int i * (Given) Axis number (1-relative), as in the FITS PSi_ma keyword. * * int m * (Given) Parameter number (non-negative), as in the FITS PSi_ma keyword. * * char value[72] * (Given) Parameter value. * * * auxprm struct - Additional auxiliary parameters * ----------------------------------------------- * The auxprm struct holds auxiliary coordinate system information of a * specialist nature. It is anticipated that this struct will expand in future * to accomodate additional parameters. * * All members of this struct are to be set by the user. * * double rsun_ref * (Given, auxiliary) Reference radius of the Sun used in coordinate * calculations (m). * * double dsun_obs * (Given, auxiliary) Distance between the centre of the Sun and the * observer (m). * * double crln_obs * (Given, auxiliary) Carrington heliographic longitude of the observer * (deg). * * double hgln_obs * (Given, auxiliary) Stonyhurst heliographic longitude of the observer * (deg). * * double hglt_obs * (Given, auxiliary) Heliographic latitude (Carrington or Stonyhurst) of * the observer (deg). * * * Global variable: const char *wcs_errmsg[] - Status return messages * ------------------------------------------------------------------ * Error messages to match the status value returned from each function. * *===========================================================================*/ #ifndef WCSLIB_WCS #define WCSLIB_WCS #include "lin.h" #include "cel.h" #include "spc.h" #ifdef __cplusplus extern "C" { #define wtbarr wtbarr_s // See prologue of wtbarr.h. #endif #define WCSSUB_LONGITUDE 0x1001 #define WCSSUB_LATITUDE 0x1002 #define WCSSUB_CUBEFACE 0x1004 #define WCSSUB_CELESTIAL 0x1007 #define WCSSUB_SPECTRAL 0x1008 #define WCSSUB_STOKES 0x1010 #define WCSSUB_TIME 0x1020 #define WCSCOMPARE_ANCILLARY 0x0001 #define WCSCOMPARE_TILING 0x0002 #define WCSCOMPARE_CRPIX 0x0004 extern const char *wcs_errmsg[]; enum wcs_errmsg_enum { WCSERR_SUCCESS = 0, // Success. WCSERR_NULL_POINTER = 1, // Null wcsprm pointer passed. WCSERR_MEMORY = 2, // Memory allocation failed. WCSERR_SINGULAR_MTX = 3, // Linear transformation matrix is singular. WCSERR_BAD_CTYPE = 4, // Inconsistent or unrecognized coordinate // axis type. WCSERR_BAD_PARAM = 5, // Invalid parameter value. WCSERR_BAD_COORD_TRANS = 6, // Unrecognized coordinate transformation // parameter. WCSERR_ILL_COORD_TRANS = 7, // Ill-conditioned coordinate transformation // parameter. WCSERR_BAD_PIX = 8, // One or more of the pixel coordinates were // invalid. WCSERR_BAD_WORLD = 9, // One or more of the world coordinates were // invalid. WCSERR_BAD_WORLD_COORD = 10, // Invalid world coordinate. WCSERR_NO_SOLUTION = 11, // No solution found in the specified // interval. WCSERR_BAD_SUBIMAGE = 12, // Invalid subimage specification. WCSERR_NON_SEPARABLE = 13, // Non-separable subimage coordinate system. WCSERR_UNSET = 14 // wcsprm struct is unset. }; // Struct used for storing PVi_ma keywords. struct pvcard { int i; // Axis number, as in PVi_ma (1-relative). int m; // Parameter number, ditto (0-relative). double value; // Parameter value. }; // Size of the pvcard struct in int units, used by the Fortran wrappers. #define PVLEN (sizeof(struct pvcard)/sizeof(int)) // Struct used for storing PSi_ma keywords. struct pscard { int i; // Axis number, as in PSi_ma (1-relative). int m; // Parameter number, ditto (0-relative). char value[72]; // Parameter value. }; // Size of the pscard struct in int units, used by the Fortran wrappers. #define PSLEN (sizeof(struct pscard)/sizeof(int)) // Struct used to hold additional auxiliary parameters. struct auxprm { double rsun_ref; // Solar radius. double dsun_obs; // Distance from Sun centre to observer. double crln_obs; // Carrington heliographic lng of observer. double hgln_obs; // Stonyhurst heliographic lng of observer. double hglt_obs; // Heliographic latitude of observer. }; // Size of the auxprm struct in int units, used by the Fortran wrappers. #define AUXLEN (sizeof(struct auxprm)/sizeof(int)) struct wcsprm { // Initialization flag (see the prologue above). //-------------------------------------------------------------------------- int flag; // Set to zero to force initialization. // FITS header keyvalues to be provided (see the prologue above). //-------------------------------------------------------------------------- int naxis; // Number of axes (pixel and coordinate). double *crpix; // CRPIXja keyvalues for each pixel axis. double *pc; // PCi_ja linear transformation matrix. double *cdelt; // CDELTia keyvalues for each coord axis. double *crval; // CRVALia keyvalues for each coord axis. char (*cunit)[72]; // CUNITia keyvalues for each coord axis. char (*ctype)[72]; // CTYPEia keyvalues for each coord axis. double lonpole; // LONPOLEa keyvalue. double latpole; // LATPOLEa keyvalue. double restfrq; // RESTFRQa keyvalue. double restwav; // RESTWAVa keyvalue. int npv; // Number of PVi_ma keywords, and the int npvmax; // number for which space was allocated. struct pvcard *pv; // PVi_ma keywords for each i and m. int nps; // Number of PSi_ma keywords, and the int npsmax; // number for which space was allocated. struct pscard *ps; // PSi_ma keywords for each i and m. // Alternative header keyvalues (see the prologue above). //-------------------------------------------------------------------------- double *cd; // CDi_ja linear transformation matrix. double *crota; // CROTAi keyvalues for each coord axis. int altlin; // Alternative representations // Bit 0: PCi_ja is present, // Bit 1: CDi_ja is present, // Bit 2: CROTAi is present. int velref; // AIPS velocity code, VELREF. // Auxiliary coordinate system information of a general nature. Not // used by WCSLIB. Refer to the prologue comments above for a brief // explanation of these values. char alt[4]; int colnum; int *colax; // Auxiliary coordinate axis information. char (*cname)[72]; double *crder; double *csyer; double *czphs; double *cperi; char wcsname[72]; // Time reference system and measurement. char timesys[72], trefpos[72], trefdir[72], plephem[72]; char timeunit[72]; char dateref[72]; double mjdref[2]; double timeoffs; // Data timestamps and durations. char dateobs[72], datebeg[72], dateavg[72], dateend[72]; double mjdobs, mjdbeg, mjdavg, mjdend; double jepoch, bepoch; double tstart, tstop; double xposure, telapse; // Timing accuracy. double timsyer, timrder; double timedel, timepixr; // Spatial & celestial reference frame. double obsgeo[6]; char obsorbit[72]; char radesys[72]; double equinox; char specsys[72]; char ssysobs[72]; double velosys; double zsource; char ssyssrc[72]; double velangl; // Additional auxiliary coordinate system information of a specialist // nature. Not used by WCSLIB. Refer to the prologue comments above. struct auxprm *aux; // Coordinate lookup tables (see the prologue above). //-------------------------------------------------------------------------- int ntab; // Number of separate tables. int nwtb; // Number of wtbarr structs. struct tabprm *tab; // Tabular transformation parameters. struct wtbarr *wtb; // Array of wtbarr structs. //-------------------------------------------------------------------------- // Information derived from the FITS header keyvalues by wcsset(). //-------------------------------------------------------------------------- char lngtyp[8], lattyp[8]; // Celestial axis types, e.g. RA, DEC. int lng, lat, spec; // Longitude, latitude and spectral axis // indices (0-relative). int cubeface; // True if there is a CUBEFACE axis. int *types; // Coordinate type codes for each axis. struct linprm lin; // Linear transformation parameters. struct celprm cel; // Celestial transformation parameters. struct spcprm spc; // Spectral transformation parameters. //-------------------------------------------------------------------------- // THE REMAINDER OF THE WCSPRM STRUCT IS PRIVATE. //-------------------------------------------------------------------------- // Error handling, if enabled. //-------------------------------------------------------------------------- struct wcserr *err; // Memory management. //-------------------------------------------------------------------------- int m_flag, m_naxis; double *m_crpix, *m_pc, *m_cdelt, *m_crval; char (*m_cunit)[72], (*m_ctype)[72]; struct pvcard *m_pv; struct pscard *m_ps; double *m_cd, *m_crota; int *m_colax; char (*m_cname)[72]; double *m_crder, *m_csyer, *m_czphs, *m_cperi; struct auxprm *m_aux; struct tabprm *m_tab; struct wtbarr *m_wtb; }; // Size of the wcsprm struct in int units, used by the Fortran wrappers. #define WCSLEN (sizeof(struct wcsprm)/sizeof(int)) int wcsnpv(int n); int wcsnps(int n); int wcsini(int alloc, int naxis, struct wcsprm *wcs); int wcsinit(int alloc, int naxis, struct wcsprm *wcs, int npvmax, int npsmax, int ndpmax); int wcsauxi(int alloc, struct wcsprm *wcs); int wcssub(int alloc, const struct wcsprm *wcssrc, int *nsub, int axes[], struct wcsprm *wcsdst); int wcscompare(int cmp, double tol, const struct wcsprm *wcs1, const struct wcsprm *wcs2, int *equal); int wcsfree(struct wcsprm *wcs); int wcstrim(struct wcsprm *wcs); int wcssize(const struct wcsprm *wcs, int sizes[2]); int auxsize(const struct auxprm *aux, int sizes[2]); int wcsprt(const struct wcsprm *wcs); int wcsperr(const struct wcsprm *wcs, const char *prefix); int wcsbchk(struct wcsprm *wcs, int bounds); int wcsset(struct wcsprm *wcs); int wcsp2s(struct wcsprm *wcs, int ncoord, int nelem, const double pixcrd[], double imgcrd[], double phi[], double theta[], double world[], int stat[]); int wcss2p(struct wcsprm *wcs, int ncoord, int nelem, const double world[], double phi[], double theta[], double imgcrd[], double pixcrd[], int stat[]); int wcsmix(struct wcsprm *wcs, int mixpix, int mixcel, const double vspan[2], double vstep, int viter, double world[], double phi[], double theta[], double imgcrd[], double pixcrd[]); int wcsccs(struct wcsprm *wcs, double lng2p1, double lat2p1, double lng1p2, const char *clng, const char *clat, const char *radesys, double equinox, const char *alt); int wcssptr(struct wcsprm *wcs, int *i, char ctype[9]); const char* wcslib_version(int vers[3]); // Defined mainly for backwards compatibility, use wcssub() instead. #define wcscopy(alloc, wcssrc, wcsdst) wcssub(alloc, wcssrc, 0x0, 0x0, wcsdst) // Deprecated. #define wcsini_errmsg wcs_errmsg #define wcssub_errmsg wcs_errmsg #define wcscopy_errmsg wcs_errmsg #define wcsfree_errmsg wcs_errmsg #define wcsprt_errmsg wcs_errmsg #define wcsset_errmsg wcs_errmsg #define wcsp2s_errmsg wcs_errmsg #define wcss2p_errmsg wcs_errmsg #define wcsmix_errmsg wcs_errmsg #ifdef __cplusplus #undef wtbarr } #endif #endif // WCSLIB_WCS