00001 /*============================================================================ 00002 00003 WCSLIB 4.4 - an implementation of the FITS WCS standard. 00004 Copyright (C) 1995-2009, Mark Calabretta 00005 00006 This file is part of WCSLIB. 00007 00008 WCSLIB is free software: you can redistribute it and/or modify it under the 00009 terms of the GNU Lesser General Public License as published by the Free 00010 Software Foundation, either version 3 of the License, or (at your option) 00011 any later version. 00012 00013 WCSLIB is distributed in the hope that it will be useful, but WITHOUT ANY 00014 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 00015 FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for 00016 more details. 00017 00018 You should have received a copy of the GNU Lesser General Public License 00019 along with WCSLIB. If not, see <http://www.gnu.org/licenses/>. 00020 00021 Correspondence concerning WCSLIB may be directed to: 00022 Internet email: mcalabre@atnf.csiro.au 00023 Postal address: Dr. Mark Calabretta 00024 Australia Telescope National Facility, CSIRO 00025 PO Box 76 00026 Epping NSW 1710 00027 AUSTRALIA 00028 00029 Author: Mark Calabretta, Australia Telescope National Facility 00030 http://www.atnf.csiro.au/~mcalabre/index.html 00031 $Id: spx_8h-source.html,v 1.1 2009/09/14 20:25:24 irby Exp $ 00032 *============================================================================= 00033 * 00034 * WCSLIB 4.4 - C routines that implement the spectral coordinate systems 00035 * recognized by the FITS World Coordinate System (WCS) standard. Refer to 00036 * 00037 * "Representations of world coordinates in FITS", 00038 * Greisen, E.W., & Calabretta, M.R. 2002, A&A, 395, 1061 (Paper I) 00039 * 00040 * "Representations of spectral coordinates in FITS", 00041 * Greisen, E.W., Calabretta, M.R., Valdes, F.G., & Allen, S.L. 00042 * 2006, A&A, 446, 747 (Paper III) 00043 * 00044 * Refer to the README file provided with WCSLIB for an overview of the 00045 * library. 00046 * 00047 * 00048 * Summary of the spx routines 00049 * --------------------------- 00050 * specx() is a scalar routine that, given one spectral variable (e.g. 00051 * frequency), computes all the others (e.g. wavelength, velocity, etc.) plus 00052 * the required derivatives of each with respect to the others. The results 00053 * are returned in the spxprm struct. 00054 * 00055 * The remaining routines are all vector conversions from one spectral 00056 * variable to another. The API of these functions only differ in whether the 00057 * rest frequency or wavelength need be supplied. 00058 * 00059 * Non-linear: 00060 * - freqwave() frequency -> vacuum wavelength 00061 * - wavefreq() vacuum wavelength -> frequency 00062 * 00063 * - freqawav() frequency -> air wavelength 00064 * - awavfreq() air wavelength -> frequency 00065 * 00066 * - freqvelo() frequency -> relativistic velocity 00067 * - velofreq() relativistic velocity -> frequency 00068 * 00069 * - waveawav() vacuum wavelength -> air wavelength 00070 * - awavwave() air wavelength -> vacuum wavelength 00071 * 00072 * - wavevelo() vacuum wavelength -> relativistic velocity 00073 * - velowave() relativistic velocity -> vacuum wavelength 00074 * 00075 * - awavvelo() air wavelength -> relativistic velocity 00076 * - veloawav() relativistic velocity -> air wavelength 00077 * 00078 * Linear: 00079 * - freqafrq() frequency -> angular frequency 00080 * - afrqfreq() angular frequency -> frequency 00081 * 00082 * - freqener() frequency -> energy 00083 * - enerfreq() energy -> frequency 00084 * 00085 * - freqwavn() frequency -> wave number 00086 * - wavnfreq() wave number -> frequency 00087 * 00088 * - freqvrad() frequency -> radio velocity 00089 * - vradfreq() radio velocity -> frequency 00090 * 00091 * - wavevopt() vacuum wavelength -> optical velocity 00092 * - voptwave() optical velocity -> vacuum wavelength 00093 * 00094 * - wavezopt() vacuum wavelength -> redshift 00095 * - zoptwave() redshift -> vacuum wavelength 00096 * 00097 * - velobeta() relativistic velocity -> beta (= v/c) 00098 * - betavelo() beta (= v/c) -> relativistic velocity 00099 * 00100 * These are the workhorse routines, to be used for fast transformations. 00101 * Conversions may be done "in place" by calling the routine with the output 00102 * vector set to the input. 00103 * 00104 * Argument checking: 00105 * ------------------ 00106 * The input spectral values are only checked for values that would result 00107 * in floating point exceptions. In particular, negative frequencies and 00108 * wavelengths are allowed, as are velocities greater than the speed of 00109 * light. The same is true for the spectral parameters - rest frequency and 00110 * wavelength. 00111 * 00112 * Accuracy: 00113 * --------- 00114 * No warranty is given for the accuracy of these routines (refer to the 00115 * copyright notice); intending users must satisfy for themselves their 00116 * adequacy for the intended purpose. However, closure effectively to within 00117 * double precision rounding error was demonstrated by test routine tspec.c 00118 * which accompanies this software. 00119 * 00120 * 00121 * specx() - Spectral cross conversions (scalar) 00122 * --------------------------------------------- 00123 * Given one spectral variable specx() computes all the others, plus the 00124 * required derivatives of each with respect to the others. 00125 * 00126 * Given: 00127 * type const char* 00128 * The type of spectral variable given by spec, FREQ, 00129 * AFRQ, ENER, WAVN, VRAD, WAVE, VOPT, ZOPT, AWAV, VELO, 00130 * or BETA (case sensitive). 00131 * spec double The spectral variable given, in SI units. 00132 * restfrq, 00133 * restwav double Rest frequency [Hz] or rest wavelength in vacuo [m], 00134 * only one of which need be given. The other should be 00135 * set to zero. If both are zero, only a subset of the 00136 * spectral variables can be computed, the remainder are 00137 * set to zero. Specifically, given one of FREQ, AFRQ, 00138 * ENER, WAVN, WAVE, or AWAV the others can be computed 00139 * without knowledge of the rest frequency. Likewise, 00140 * VRAD, VOPT, ZOPT, VELO, and BETA. 00141 * 00142 * Given and returned: 00143 * specs struct spxprm* 00144 * Data structure containing all spectral variables and 00145 * their derivatives, in SI units. 00146 * 00147 * Function return value: 00148 * int Status return value: 00149 * 0: Success. 00150 * 1: Null spxprm pointer passed. 00151 * 2: Invalid spectral parameters. 00152 * 3: Invalid spectral variable. 00153 * 00154 * 00155 * freqafrq(), afrqfreq(), freqener(), enerfreq(), freqwavn(), wavnfreq(), 00156 * freqwave(), wavefreq(), freqawav(), awavfreq(), waveawav(), awavwave(), 00157 * velobeta(), and betavelo() implement vector conversions between wave-like 00158 * or velocity-like spectral types (i.e. conversions that do not need the rest 00159 * frequency or wavelength). They all have the same API. 00160 * 00161 * 00162 * freqafrq() - Convert frequency to angular frequency (vector) 00163 * ------------------------------------------------------------ 00164 * freqafrq() converts frequency to angular frequency. 00165 * 00166 * Given: 00167 * param double Ignored. 00168 * nspec int Vector length. 00169 * instep, 00170 * outstep int Vector strides. 00171 * inspec const double[] 00172 * Input spectral variables, in SI units. 00173 * 00174 * Returned: 00175 * outspec double[] Output spectral variables, in SI units. 00176 * stat int[] Status return value for each vector element: 00177 * 0: Success. 00178 * 1: Invalid value of inspec. 00179 * 00180 * Function return value: 00181 * int Status return value: 00182 * 0: Success. 00183 * 2: Invalid spectral parameters. 00184 * 4: One or more of the inspec coordinates were 00185 * invalid, as indicated by the stat vector. 00186 * 00187 * 00188 * freqvelo(), velofreq(), freqvrad(), and vradfreq() implement vector 00189 * conversions between frequency and velocity spectral types. They all have 00190 * the same API. 00191 * 00192 * 00193 * freqvelo() - Convert frequency to relativistic velocity (vector) 00194 * ---------------------------------------------------------------- 00195 * freqvelo() converts frequency to relativistic velocity. 00196 * 00197 * Given: 00198 * param double Rest frequency [Hz]. 00199 * nspec int Vector length. 00200 * instep, 00201 * outstep int Vector strides. 00202 * inspec const double[] 00203 * Input spectral variables, in SI units. 00204 * 00205 * Returned: 00206 * outspec double[] Output spectral variables, in SI units. 00207 * stat int[] Status return value for each vector element: 00208 * 0: Success. 00209 * 1: Invalid value of inspec. 00210 * 00211 * Function return value: 00212 * int Status return value: 00213 * 0: Success. 00214 * 2: Invalid spectral parameters. 00215 * 4: One or more of the inspec coordinates were 00216 * invalid, as indicated by the stat vector. 00217 * 00218 * 00219 * wavevelo(), velowave(), awavvelo(), veloawav(), wavevopt(), voptwave(), 00220 * wavezopt(), and zoptwave() implement vector conversions between wavelength 00221 * and velocity spectral types. They all have the same API. 00222 * 00223 * 00224 * wavevelo() - Conversions between wavelength and velocity types (vector) 00225 * ----------------------------------------------------------------------- 00226 * wavevelo() converts vacuum wavelength to relativistic velocity. 00227 * 00228 * Given: 00229 * param double Rest wavelength in vacuo [m]. 00230 * nspec int Vector length. 00231 * instep, 00232 * outstep int Vector strides. 00233 * inspec const double[] 00234 * Input spectral variables, in SI units. 00235 * 00236 * Returned: 00237 * outspec double[] Output spectral variables, in SI units. 00238 * stat int[] Status return value for each vector element: 00239 * 0: Success. 00240 * 1: Invalid value of inspec. 00241 * 00242 * Function return value: 00243 * int Status return value: 00244 * 0: Success. 00245 * 2: Invalid spectral parameters. 00246 * 4: One or more of the inspec coordinates were 00247 * invalid, as indicated by the stat vector. 00248 * 00249 * 00250 * spxprm struct - Spectral variables and their derivatives 00251 * -------------------------------------------------------- 00252 * The spxprm struct contains the value of all spectral variables and their 00253 * derivatives. It is used solely by specx() which constructs it from 00254 * information provided via its function arguments. 00255 * 00256 * This struct should be considered read-only, no members need ever be set nor 00257 * should ever be modified by the user. 00258 * 00259 * double restfrq 00260 * (Returned) Rest frequency [Hz]. 00261 * 00262 * double restwav 00263 * (Returned) Rest wavelength [m]. 00264 * 00265 * int wavetype 00266 * (Returned) True if wave types have been computed, and ... 00267 * 00268 * int velotype 00269 * (Returned) ... true if velocity types have been computed; types are 00270 * defined below. 00271 * 00272 * If one or other of spxprm::restfrq and spxprm::restwav is given 00273 * (non-zero) then all spectral variables may be computed. If both are 00274 * given, restfrq is used. If restfrq and restwav are both zero, only wave 00275 * characteristic xor velocity type spectral variables may be computed 00276 * depending on the variable given. These flags indicate what is 00277 * available. 00278 * 00279 * double freq 00280 * (Returned) Frequency [Hz] (wavetype). 00281 * 00282 * double afrq 00283 * (Returned) Angular frequency [rad/s] (wavetype). 00284 * 00285 * double ener 00286 * (Returned) Photon energy [J] (wavetype). 00287 * 00288 * double wavn 00289 * (Returned) Wave number [/m] (wavetype). 00290 * 00291 * double vrad 00292 * (Returned) Radio velocity [m/s] (velotype). 00293 * 00294 * double wave 00295 * (Returned) Vacuum wavelength [m] (wavetype). 00296 * 00297 * double vopt 00298 * (Returned) Optical velocity [m/s] (velotype). 00299 * 00300 * double zopt 00301 * (Returned) Redshift [dimensionless] (velotype). 00302 * 00303 * double awav 00304 * (Returned) Air wavelength [m] (wavetype). 00305 * 00306 * double velo 00307 * (Returned) Relativistic velocity [m/s] (velotype). 00308 * 00309 * double beta 00310 * (Returned) Relativistic beta [dimensionless] (velotype). 00311 * 00312 * double dfreqafrq 00313 * (Returned) Derivative of frequency with respect to angular frequency 00314 * [/rad] (constant, = 1 / 2*pi), and ... 00315 * double dafrqfreq 00316 * (Returned) ... vice versa [rad] (constant, = 2*pi, always available). 00317 * 00318 * double dfreqener 00319 * (Returned) Derivative of frequency with respect to photon energy 00320 * [/J/s] (constant, = 1/h), and ... 00321 * double denerfreq 00322 * (Returned) ... vice versa [Js] (constant, = h, Planck's constant, 00323 * always available). 00324 * 00325 * double dfreqwavn 00326 * (Returned) Derivative of frequency with respect to wave number [m/s] 00327 * (constant, = c, the speed of light in vacuuo), and ... 00328 * double dwavnfreq 00329 * (Returned) ... vice versa [s/m] (constant, = 1/c, always available). 00330 * 00331 * double dfreqvrad 00332 * (Returned) Derivative of frequency with respect to radio velocity [/m], 00333 * and ... 00334 * double dvradfreq 00335 * (Returned) ... vice versa [m] (wavetype && velotype). 00336 * 00337 * double dfreqwave 00338 * (Returned) Derivative of frequency with respect to vacuum wavelength 00339 * [/m/s], and ... 00340 * double dwavefreq 00341 * (Returned) ... vice versa [m s] (wavetype). 00342 * 00343 * double dfreqawav 00344 * (Returned) Derivative of frequency with respect to air wavelength, 00345 * [/m/s], and ... 00346 * double dawavfreq 00347 * (Returned) ... vice versa [m s] (wavetype). 00348 * 00349 * double dfreqvelo 00350 * (Returned) Derivative of frequency with respect to relativistic 00351 * velocity [/m], and ... 00352 * double dvelofreq 00353 * (Returned) ... vice versa [m] (wavetype && velotype). 00354 * 00355 * double dwavevopt 00356 * (Returned) Derivative of vacuum wavelength with respect to optical 00357 * velocity [s], and ... 00358 * double dvoptwave 00359 * (Returned) ... vice versa [/s] (wavetype && velotype). 00360 * 00361 * double dwavezopt 00362 * (Returned) Derivative of vacuum wavelength with respect to redshift [m], 00363 * and ... 00364 * double dzoptwave 00365 * (Returned) ... vice versa [/m] (wavetype && velotype). 00366 * 00367 * double dwaveawav 00368 * (Returned) Derivative of vacuum wavelength with respect to air 00369 * wavelength [dimensionless], and ... 00370 * double dawavwave 00371 * (Returned) ... vice versa [dimensionless] (wavetype). 00372 * 00373 * double dwavevelo 00374 * (Returned) Derivative of vacuum wavelength with respect to relativistic 00375 * velocity [s], and ... 00376 * double dvelowave 00377 * (Returned) ... vice versa [/s] (wavetype && velotype). 00378 * 00379 * double dawavvelo 00380 * (Returned) Derivative of air wavelength with respect to relativistic 00381 * velocity [s], and ... 00382 * double dveloawav 00383 * (Returned) ... vice versa [/s] (wavetype && velotype). 00384 * 00385 * double dvelobeta 00386 * (Returned) Derivative of relativistic velocity with respect to 00387 * relativistic beta [m/s] (constant, = c, the speed of light in vacuu0), 00388 * and ... 00389 * double dbetavelo 00390 * (Returned) ... vice versa [s/m] (constant, = 1/c, always available). 00391 * 00392 * 00393 * Global variable: const char *spx_errmsg[] - Status return messages 00394 * ------------------------------------------------------------------ 00395 * Error messages to match the status value returned from each function. 00396 * 00397 *===========================================================================*/ 00398 00399 #ifndef WCSLIB_SPEC 00400 #define WCSLIB_SPEC 00401 00402 #ifdef __cplusplus 00403 extern "C" { 00404 #endif 00405 00406 00407 extern const char *spx_errmsg[]; 00408 00409 00410 struct spxprm { 00411 double restfrq, restwav; /* Rest frequency [Hz] and wavelength [m]. */ 00412 00413 int wavetype, velotype; /* True if wave/velocity types have been */ 00414 /* computed; types are defined below. */ 00415 00416 /* Spectral variables computed by specx(). */ 00417 /*------------------------------------------------------------------------*/ 00418 double freq, /* wavetype: Frequency [Hz]. */ 00419 afrq, /* wavetype: Angular frequency [rad/s]. */ 00420 ener, /* wavetype: Photon energy [J]. */ 00421 wavn, /* wavetype: Wave number [/m]. */ 00422 vrad, /* velotype: Radio velocity [m/s]. */ 00423 wave, /* wavetype: Vacuum wavelength [m]. */ 00424 vopt, /* velotype: Optical velocity [m/s]. */ 00425 zopt, /* velotype: Redshift. */ 00426 awav, /* wavetype: Air wavelength [m]. */ 00427 velo, /* velotype: Relativistic velocity [m/s]. */ 00428 beta; /* velotype: Relativistic beta. */ 00429 00430 /* Derivatives of spectral variables computed by specx(). */ 00431 /*------------------------------------------------------------------------*/ 00432 double dfreqafrq, dafrqfreq, /* Constant, always available. */ 00433 dfreqener, denerfreq, /* Constant, always available. */ 00434 dfreqwavn, dwavnfreq, /* Constant, always available. */ 00435 dfreqvrad, dvradfreq, /* wavetype && velotype. */ 00436 dfreqwave, dwavefreq, /* wavetype. */ 00437 dfreqawav, dawavfreq, /* wavetype. */ 00438 dfreqvelo, dvelofreq, /* wavetype && velotype. */ 00439 dwavevopt, dvoptwave, /* wavetype && velotype. */ 00440 dwavezopt, dzoptwave, /* wavetype && velotype. */ 00441 dwaveawav, dawavwave, /* wavetype. */ 00442 dwavevelo, dvelowave, /* wavetype && velotype. */ 00443 dawavvelo, dveloawav, /* wavetype && velotype. */ 00444 dvelobeta, dbetavelo; /* Constant, always available. */ 00445 }; 00446 00447 /* Size of the spxprm struct in int units, used by the Fortran wrappers. */ 00448 #define SPXLEN (sizeof(struct spxprm)/sizeof(int)) 00449 00450 00451 int specx(const char *type, double spec, double restfrq, double restwav, 00452 struct spxprm *specs); 00453 00454 00455 /* For use in declaring function prototypes, e.g. in spcprm. */ 00456 #define SPX_ARGS double param, int nspec, int instep, int outstep, \ 00457 const double inspec[], double outspec[], int stat[] 00458 00459 int freqafrq(SPX_ARGS); 00460 int afrqfreq(SPX_ARGS); 00461 00462 int freqener(SPX_ARGS); 00463 int enerfreq(SPX_ARGS); 00464 00465 int freqwavn(SPX_ARGS); 00466 int wavnfreq(SPX_ARGS); 00467 00468 int freqwave(SPX_ARGS); 00469 int wavefreq(SPX_ARGS); 00470 00471 int freqawav(SPX_ARGS); 00472 int awavfreq(SPX_ARGS); 00473 00474 int waveawav(SPX_ARGS); 00475 int awavwave(SPX_ARGS); 00476 00477 int velobeta(SPX_ARGS); 00478 int betavelo(SPX_ARGS); 00479 00480 00481 int freqvelo(SPX_ARGS); 00482 int velofreq(SPX_ARGS); 00483 00484 int freqvrad(SPX_ARGS); 00485 int vradfreq(SPX_ARGS); 00486 00487 00488 int wavevelo(SPX_ARGS); 00489 int velowave(SPX_ARGS); 00490 00491 int awavvelo(SPX_ARGS); 00492 int veloawav(SPX_ARGS); 00493 00494 int wavevopt(SPX_ARGS); 00495 int voptwave(SPX_ARGS); 00496 00497 int wavezopt(SPX_ARGS); 00498 int zoptwave(SPX_ARGS); 00499 00500 00501 #ifdef __cplusplus 00502 } 00503 #endif 00504 00505 #endif /* WCSLIB_SPEC */
1.5.1