Astro-PAL
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erfasrc/src/plan94.c view on Meta::CPAN
** Derived, with permission, from the SOFA library. See notes at end of file.
*/
{
/* Gaussian constant */
static const double GK = 0.017202098950;
/* Sin and cos of J2000.0 mean obliquity (IAU 1976) */
static const double SINEPS = 0.3977771559319137;
static const double COSEPS = 0.9174820620691818;
/* Maximum number of iterations allowed to solve Kepler's equation */
static const int KMAX = 10;
int jstat, i, k;
double t, da, dl, de, dp, di, dom, dmu, arga, argl, am,
ae, dae, ae2, at, r, v, si2, xq, xp, tl, xsw,
xcw, xm2, xf, ci2, xms, xmc, xpxq2, x, y, z;
/* Planetary inverse masses */
static const double amas[] = { 6023600.0, /* Mercury */
408523.5, /* Venus */
erfasrc/src/pmsafe.c view on Meta::CPAN
** but not so large that the proper motion is equivalent to a large
** but safe speed (about 0.1c using the chosen constant). A warning
** status of 1 is added to the status if this action has been taken.
**
** 7) If the space velocity is a significant fraction of c (see the
** constant VMAX in the function eraStarpv), it is arbitrarily set
** to zero. When this action occurs, 2 is added to the status.
**
** 8) The relativistic adjustment carried out in the eraStarpv function
** involves an iterative calculation. If the process fails to
** converge within a set number of iterations, 4 is added to the
** status.
**
** Called:
** eraSeps angle between two points
** eraStarpm update star catalog data for space motion
**
** Copyright (C) 2013-2020, NumFOCUS Foundation.
** Derived, with permission, from the SOFA library. See notes at end of file.
*/
{
erfasrc/src/starpm.c view on Meta::CPAN
** of which is an arbitrary (large) value (see the eraStarpv
** function for the value used). When the distance is overridden in
** this way, the status, initially zero, has 1 added to it.
**
** 7) If the space velocity is a significant fraction of c (see the
** constant VMAX in the function eraStarpv), it is arbitrarily set
** to zero. When this action occurs, 2 is added to the status.
**
** 8) The relativistic adjustment carried out in the eraStarpv function
** involves an iterative calculation. If the process fails to
** converge within a set number of iterations, 4 is added to the
** status.
**
** Called:
** eraStarpv star catalog data to space motion pv-vector
** eraPvu update a pv-vector
** eraPdp scalar product of two p-vectors
** eraPvstar space motion pv-vector to star catalog data
**
** Copyright (C) 2013-2020, NumFOCUS Foundation.
** Derived, with permission, from the SOFA library. See notes at end of file.
erfasrc/src/starpv.c view on Meta::CPAN
** of which is an arbitrary (large) value (see the constant PXMIN).
** When the distance is overridden in this way, the status,
** initially zero, has 1 added to it.
**
** 7) If the space velocity is a significant fraction of c (see the
** constant VMAX), it is arbitrarily set to zero. When this action
** occurs, 2 is added to the status.
**
** 8) The relativistic adjustment involves an iterative calculation.
** If the process fails to converge within a set number (IMAX) of
** iterations, 4 is added to the status.
**
** 9) The inverse transformation is performed by the function
** eraPvstar.
**
** Called:
** eraS2pv spherical coordinates to pv-vector
** eraPm modulus of p-vector
** eraZp zero p-vector
** eraPn decompose p-vector into modulus and direction
** eraPdp scalar product of two p-vectors
erfasrc/src/starpv.c view on Meta::CPAN
** Copyright (C) 2013-2020, NumFOCUS Foundation.
** Derived, with permission, from the SOFA library. See notes at end of file.
*/
{
/* Smallest allowed parallax */
static const double PXMIN = 1e-7;
/* Largest allowed speed (fraction of c) */
static const double VMAX = 0.5;
/* Maximum number of iterations for relativistic solution */
static const int IMAX = 100;
int i, iwarn;
double w, r, rd, rad, decd, v, x[3], usr[3], ust[3],
vsr, vst, betst, betsr, bett, betr,
dd, ddel, ur[3], ut[3],
d = 0.0, del = 0.0, /* to prevent */
odd = 0.0, oddel = 0.0, /* compiler */
od = 0.0, odel = 0.0; /* warnings */
palsrc/palAopqk.c view on Meta::CPAN
/* fast algorithm using two constant model */
refa = aoprms[10];
refb = aoprms[11];
palRefz(zdt,refa,refb,&zdobs);
/* large zenith distance? */
if (cos(zdobs) < zbreak) {
/* yes: use rigorous algorithm */
/* initialize loop (maximum of 10 iterations) */
i = 1;
dzd = 1.0e1;
while (fabs(dzd) > 1e-10 && i <= 10) {
/* compute refraction using current estimate of observed zd */
palRefro(zdobs,aoprms[4],aoprms[5],aoprms[6],
aoprms[7],aoprms[8],aoprms[0],
aoprms[9],1e-8,&dref);
/* remaining discrepancy */
palsrc/palRefro.c view on Meta::CPAN
fs = refi(dns,rdndrs);
/* variable initialization to avoid compiler warning. */
reft = 0.0;
/* integrate the refraction integral in two parts; first in the
* troposphere (k=1), then in the stratosphere (k=2). */
for (k=1; k<=2; k++) {
/* initialize previous refraction to ensure at least two iterations. */
refold = 1.0;
/* start off with 8 strips. */
is = 8;
/* start z, z range, and start and end values. */
if (k==1) {
z0 = zobs2;
zrange = zt-z0;
fb = f0;
palsrc/palRefro.c view on Meta::CPAN
} else {
r = rt;
}
/* one pass (no need to compute evens after first time). */
for (i=1; i<is; i+=n) {
/* sine of observed zenith distance. */
sz = sin(z0+h*(double)(i));
/* find r (to the nearest metre, maximum four iterations). */
if (sz > 1e-20) {
w = sk0/sz;
rg = r;
dr = 1.0e6;
j = 0;
while ( fabs(dr) > 1.0 && j < 4 ) {
j++;
if (k==1) {
pal1Atmt(r0,tdkok,alpha,gamm2,delm2,
c1,c2,c3,c4,c5,c6,rg,&tg,&dn,&rdndr);
palsrc/palRefz.c view on Meta::CPAN
* Notes:
* - This routine applies the adjustment for refraction in the
* opposite sense to the usual one - it takes an unrefracted
* (in vacuo) position and produces an observed (refracted)
* position, whereas the A tan Z + B tan**3 Z model strictly
* applies to the case where an observed position is to have the
* refraction removed. The unrefracted to refracted case is
* harder, and requires an inverted form of the text-book
* refraction models; the formula used here is based on the
* Newton-Raphson method. For the utmost numerical consistency
* with the refracted to unrefracted model, two iterations are
* carried out, achieving agreement at the 1D-11 arcseconds level
* for a ZD of 80 degrees. The inherent accuracy of the model
* is, of course, far worse than this - see the documentation for
* palRefco for more information.
*
* - At ZD 83 degrees, the rapidly-worsening A tan Z + B tan^3 Z
* model is abandoned and an empirical formula takes over. For
* optical/IR wavelengths, over a wide range of observer heights and
* corresponding temperatures and pressures, the following levels of
* accuracy (arcsec, worst case) are achieved, relative to numerical
palsrc/palUe2pv.c view on Meta::CPAN
#include <math.h>
#include "pal.h"
#include "palmac.h"
void palUe2pv( double date, double u[13], double pv[6], int *jstat ) {
/* Canonical days to seconds */
const double CD2S = PAL__GCON / PAL__SPD;
/* Test value for solution and maximum number of iterations */
const double TEST = 1e-13;
const int NITMAX = 25;
int I, NIT, N;
double CM,ALPHA,T0,P0[3],V0[3],R0,SIGMA0,T,PSI,DT,W,
TOL,PSJ,PSJ2,BETA,S0,S1,S2,S3,
FF,R,F,G,FD,GD;
double PLAST = 0.0;
double FLAST = 0.0;
( run in 0.771 second using v1.01-cache-2.11-cpan-96521ef73a4 )