1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
|
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
<!--Converted with LaTeX2HTML 97.1 (release) (July 13th, 1997)
by Nikos Drakos (nikos@cbl.leeds.ac.uk), CBLU, University of Leeds
* revised and updated by: Marcus Hennecke, Ross Moore, Herb Swan
* with significant contributions from:
Jens Lippman, Marek Rouchal, Martin Wilck and others -->
<HTML>
<HEAD>
<TITLE>SLALIB -- Positional Astronomy Library</TITLE>
<META NAME="description" CONTENT="SLALIB -- Positional Astronomy Library">
<META NAME="keywords" CONTENT="sun67">
<META NAME="resource-type" CONTENT="document">
<META NAME="distribution" CONTENT="global">
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso_8859_1">
<LINK REL="STYLESHEET" HREF="sun67.css">
<LINK REL="next" HREF="node1.html">
</HEAD>
<BODY >
<BR> <HR>
<A NAME="tex2html7" HREF="node1.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A>
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif_gr.gif">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif_gr.gif"> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0"
SRC="contents_motif.gif"></A>
<BR>
<B> Next:</B> <A NAME="tex2html8" HREF="node1.html">Abstract</A>
<BR>
<BR> <HR> <P>
<P><!--End of Navigation Panel-->
<P><A NAME="xref_"> </A>
<H1>
SLALIB -- Positional Astronomy Library
<BR>
2.4-0
<BR>
Programmer's Manual
</H1>
<P> <P> <I>
Starlink User Note67.45
<BR>
P.T.Wallace
<BR>
12 October 1999
</I> </P> <H3>
<A NAME="tex2html1" HREF="http://www.cclrc.ac.uk">CCLRC</A>
/
<A NAME="tex2html1" HREF="http://www.cclrc.ac.uk/ral">Rutherford Appleton Laboratory</A>
<BR>
<A NAME="tex2html1" HREF="http://www.pparc.ac.uk">Particle Physics & Astronomy Research Council</A>
<BR>
</H3> <H2>
<A NAME="tex2html1" HREF="http://star-www.rl.ac.uk/">Starlink Project</A>
</H2>
<A NAME="tex2html1" HREF="http://star-www.rl.ac.uk/cgi-bin/hcserver?sun67.45"><IMG ALIGN="BOTTOM" BORDER="0"
SRC="source.gif"> Retrieve hardcopy</A>
<BR>
<A NAME="stardoccontents"> </A> <HR>
<H2>Contents</H2>
<P> <BR><HR>
<!--Table of Child-Links-->
<A NAME="CHILD_LINKS"> </A>
<UL>
<LI><A NAME="tex2html9" HREF="node1.html#SECTION00010000000000000000">
Abstract</A>
<LI><A NAME="tex2html10" HREF="node2.html#SECTION00020000000000000000">
INTRODUCTION</A>
<UL>
<LI><A NAME="tex2html11" HREF="node3.html#SECTION00021000000000000000">
Purpose</A>
<LI><A NAME="tex2html12" HREF="node4.html#SECTION00022000000000000000">
Example Application</A>
<LI><A NAME="tex2html13" HREF="node5.html#SECTION00023000000000000000">
Scope</A>
<LI><A NAME="tex2html14" HREF="node6.html#SECTION00024000000000000000">
Objectives</A>
<LI><A NAME="tex2html15" HREF="node7.html#SECTION00025000000000000000">
Fortran Version</A>
<LI><A NAME="tex2html16" HREF="node8.html#SECTION00026000000000000000">
C Version</A>
<LI><A NAME="tex2html17" HREF="node9.html#SECTION00027000000000000000">
Future Versions</A>
<LI><A NAME="tex2html18" HREF="node10.html#SECTION00028000000000000000">
New Functions</A>
<LI><A NAME="tex2html19" HREF="node11.html#SECTION00029000000000000000">
Acknowledgements</A>
</UL>
<LI><A NAME="tex2html20" HREF="node12.html#SECTION00030000000000000000">
LINKING</A>
<LI><A NAME="tex2html21" HREF="node13.html#SECTION00040000000000000000">
SUBPROGRAM SPECIFICATIONS</A>
<UL>
<LI><A NAME="tex2html22" HREF="node14.html#SECTION00041000000000000000">
SLA_ADDET - Add E-terms of Aberration</A>
<LI><A NAME="tex2html23" HREF="node15.html#SECTION00042000000000000000">
SLA_AFIN - Sexagesimal character string to angle</A>
<LI><A NAME="tex2html24" HREF="node16.html#SECTION00043000000000000000">
SLA_AIRMAS - Air Mass</A>
<LI><A NAME="tex2html25" HREF="node17.html#SECTION00044000000000000000">
SLA_ALTAZ - Velocities <I>etc.</I> for Altazimuth Mount</A>
<LI><A NAME="tex2html26" HREF="node18.html#SECTION00045000000000000000">
SLA_AMP - Apparent to Mean</A>
<LI><A NAME="tex2html27" HREF="node19.html#SECTION00046000000000000000">
SLA_AMPQK - Quick Apparent to Mean</A>
<LI><A NAME="tex2html28" HREF="node20.html#SECTION00047000000000000000">
SLA_AOP - Apparent to Observed</A>
<LI><A NAME="tex2html29" HREF="node21.html#SECTION00048000000000000000">
SLA_AOPPA - Appt-to-Obs Parameters</A>
<LI><A NAME="tex2html30" HREF="node22.html#SECTION00049000000000000000">
SLA_AOPPAT - Update Appt-to-Obs Parameters</A>
<LI><A NAME="tex2html31" HREF="node23.html#SECTION000410000000000000000">
SLA_AOPQK - Quick Appt-to-Observed</A>
<LI><A NAME="tex2html32" HREF="node24.html#SECTION000411000000000000000">
SLA_ATMDSP - Atmospheric Dispersion</A>
<LI><A NAME="tex2html33" HREF="node25.html#SECTION000412000000000000000">
SLA_AV2M - Rotation Matrix from Axial Vector</A>
<LI><A NAME="tex2html34" HREF="node26.html#SECTION000413000000000000000">
SLA_BEAR - Direction Between Points on a Sphere</A>
<LI><A NAME="tex2html35" HREF="node27.html#SECTION000414000000000000000">
SLA_CAF2R - Deg,Arcmin,Arcsec to Radians</A>
<LI><A NAME="tex2html36" HREF="node28.html#SECTION000415000000000000000">
SLA_CALDJ - Calendar Date to MJD</A>
<LI><A NAME="tex2html37" HREF="node29.html#SECTION000416000000000000000">
SLA_CALYD - Calendar to Year, Day</A>
<LI><A NAME="tex2html38" HREF="node30.html#SECTION000417000000000000000">
SLA_CC2S - Cartesian to Spherical</A>
<LI><A NAME="tex2html39" HREF="node31.html#SECTION000418000000000000000">
SLA_CC62S - Cartesian 6-Vector to Spherical</A>
<LI><A NAME="tex2html40" HREF="node32.html#SECTION000419000000000000000">
SLA_CD2TF - Days to Hour,Min,Sec</A>
<LI><A NAME="tex2html41" HREF="node33.html#SECTION000420000000000000000">
SLA_CLDJ - Calendar to MJD</A>
<LI><A NAME="tex2html42" HREF="node34.html#SECTION000421000000000000000">
SLA_CLYD - Calendar to Year, Day</A>
<LI><A NAME="tex2html43" HREF="node35.html#SECTION000422000000000000000">
SLA_COMBN - Next Combination</A>
<LI><A NAME="tex2html44" HREF="node36.html#SECTION000423000000000000000">
SLA_CR2AF - Radians to Deg,Arcmin,Arcsec</A>
<LI><A NAME="tex2html45" HREF="node37.html#SECTION000424000000000000000">
SLA_CR2TF - Radians to Hour,Min,Sec</A>
<LI><A NAME="tex2html46" HREF="node38.html#SECTION000425000000000000000">
SLA_CS2C - Spherical to Cartesian</A>
<LI><A NAME="tex2html47" HREF="node39.html#SECTION000426000000000000000">
SLA_CS2C6 - Spherical Pos/Vel to Cartesian</A>
<LI><A NAME="tex2html48" HREF="node40.html#SECTION000427000000000000000">
SLA_CTF2D - Hour,Min,Sec to Days</A>
<LI><A NAME="tex2html49" HREF="node41.html#SECTION000428000000000000000">
SLA_CTF2R - Hour,Min,Sec to Radians</A>
<LI><A NAME="tex2html50" HREF="node42.html#SECTION000429000000000000000">
SLA_DAF2R - Deg,Arcmin,Arcsec to Radians</A>
<LI><A NAME="tex2html51" HREF="node43.html#SECTION000430000000000000000">
SLA_DAFIN - Sexagesimal character string to angle</A>
<LI><A NAME="tex2html52" HREF="node44.html#SECTION000431000000000000000">
SLA_DAT - TAI-UTC</A>
<LI><A NAME="tex2html53" HREF="node45.html#SECTION000432000000000000000">
SLA_DAV2M - Rotation Matrix from Axial Vector</A>
<LI><A NAME="tex2html54" HREF="node46.html#SECTION000433000000000000000">
SLA_DBEAR - Direction Between Points on a Sphere</A>
<LI><A NAME="tex2html55" HREF="node47.html#SECTION000434000000000000000">
SLA_DBJIN - Decode String to B/J Epoch (DP)</A>
<LI><A NAME="tex2html56" HREF="node48.html#SECTION000435000000000000000">
SLA_DC62S - Cartesian 6-Vector to Spherical</A>
<LI><A NAME="tex2html57" HREF="node49.html#SECTION000436000000000000000">
SLA_DCC2S - Cartesian to Spherical</A>
<LI><A NAME="tex2html58" HREF="node50.html#SECTION000437000000000000000">
SLA_DCMPF - Interpret Linear Fit</A>
<LI><A NAME="tex2html59" HREF="node51.html#SECTION000438000000000000000">
SLA_DCS2C - Spherical to Cartesian</A>
<LI><A NAME="tex2html60" HREF="node52.html#SECTION000439000000000000000">
SLA_DD2TF - Days to Hour,Min,Sec</A>
<LI><A NAME="tex2html61" HREF="node53.html#SECTION000440000000000000000">
SLA_DE2H - <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img65.gif"
ALT="$h,\delta$"> to Az,El</A>
<LI><A NAME="tex2html62" HREF="node54.html#SECTION000441000000000000000">
SLA_DEULER - Euler Angles to Rotation Matrix</A>
<LI><A NAME="tex2html63" HREF="node55.html#SECTION000442000000000000000">
SLA_DFLTIN - Decode a Double Precision Number</A>
<LI><A NAME="tex2html64" HREF="node56.html#SECTION000443000000000000000">
SLA_DH2E - Az,El to <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img65.gif"
ALT="$h,\delta$"></A>
<LI><A NAME="tex2html65" HREF="node57.html#SECTION000444000000000000000">
SLA_DIMXV - Apply 3D Reverse Rotation</A>
<LI><A NAME="tex2html66" HREF="node58.html#SECTION000445000000000000000">
SLA_DJCAL - MJD to Gregorian for Output</A>
<LI><A NAME="tex2html67" HREF="node59.html#SECTION000446000000000000000">
SLA_DJCL - MJD to Year,Month,Day,Frac</A>
<LI><A NAME="tex2html68" HREF="node60.html#SECTION000447000000000000000">
SLA_DM2AV - Rotation Matrix to Axial Vector</A>
<LI><A NAME="tex2html69" HREF="node61.html#SECTION000448000000000000000">
SLA_DMAT - Solve Simultaneous Equations</A>
<LI><A NAME="tex2html70" HREF="node62.html#SECTION000449000000000000000">
SLA_DMOON - Approx Moon Pos/Vel</A>
<LI><A NAME="tex2html71" HREF="node63.html#SECTION000450000000000000000">
SLA_DMXM - Multiply <IMG WIDTH="39" HEIGHT="25" ALIGN="MIDDLE" BORDER="0"
SRC="img18.gif"
ALT="$3\times3$"> Matrices</A>
<LI><A NAME="tex2html72" HREF="node64.html#SECTION000451000000000000000">
SLA_DMXV - Apply 3D Rotation</A>
<LI><A NAME="tex2html73" HREF="node65.html#SECTION000452000000000000000">
SLA_DPAV - Position-Angle Between Two Directions</A>
<LI><A NAME="tex2html74" HREF="node66.html#SECTION000453000000000000000">
SLA_DR2AF - Radians to Deg,Min,Sec,Frac</A>
<LI><A NAME="tex2html75" HREF="node67.html#SECTION000454000000000000000">
SLA_DR2TF - Radians to Hour,Min,Sec,Frac</A>
<LI><A NAME="tex2html76" HREF="node68.html#SECTION000455000000000000000">
SLA_DRANGE - Put Angle into Range <IMG WIDTH="25" HEIGHT="25" ALIGN="MIDDLE" BORDER="0"
SRC="img47.gif"
ALT="$\pm \pi$"></A>
<LI><A NAME="tex2html77" HREF="node69.html#SECTION000456000000000000000">
SLA_DRANRM - Put Angle into Range <IMG WIDTH="43" HEIGHT="25" ALIGN="MIDDLE" BORDER="0"
SRC="img66.gif"
ALT="$0\!-\!2\pi$"></A>
<LI><A NAME="tex2html78" HREF="node70.html#SECTION000457000000000000000">
SLA_DS2C6 - Spherical Pos/Vel to Cartesian</A>
<LI><A NAME="tex2html79" HREF="node71.html#SECTION000458000000000000000">
SLA_DS2TP - Spherical to Tangent Plane</A>
<LI><A NAME="tex2html80" HREF="node72.html#SECTION000459000000000000000">
SLA_DSEP - Angle Between 2 Points on Sphere</A>
<LI><A NAME="tex2html81" HREF="node73.html#SECTION000460000000000000000">
SLA_DT - Approximate ET minus UT</A>
<LI><A NAME="tex2html82" HREF="node74.html#SECTION000461000000000000000">
SLA_DTF2D - Hour,Min,Sec to Days</A>
<LI><A NAME="tex2html83" HREF="node75.html#SECTION000462000000000000000">
SLA_DTF2R - Hour,Min,Sec to Radians</A>
<LI><A NAME="tex2html84" HREF="node76.html#SECTION000463000000000000000">
SLA_DTP2S - Tangent Plane to Spherical</A>
<LI><A NAME="tex2html85" HREF="node77.html#SECTION000464000000000000000">
SLA_DTP2V - Tangent Plane to Direction Cosines</A>
<LI><A NAME="tex2html86" HREF="node78.html#SECTION000465000000000000000">
SLA_DTPS2C - Plate centre from <IMG WIDTH="26" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img90.gif"
ALT="$\xi,\eta$"> and <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"></A>
<LI><A NAME="tex2html87" HREF="node79.html#SECTION000466000000000000000">
SLA_DTPV2C - Plate centre from <IMG WIDTH="26" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img90.gif"
ALT="$\xi,\eta$"> and <I>x</I>,<I>y</I>,<I>z</I></A>
<LI><A NAME="tex2html88" HREF="node80.html#SECTION000467000000000000000">
SLA_DTT - TT minus UTC</A>
<LI><A NAME="tex2html89" HREF="node81.html#SECTION000468000000000000000">
SLA_DV2TP - Direction Cosines to Tangent Plane</A>
<LI><A NAME="tex2html90" HREF="node82.html#SECTION000469000000000000000">
SLA_DVDV - Scalar Product</A>
<LI><A NAME="tex2html91" HREF="node83.html#SECTION000470000000000000000">
SLA_DVN - Normalize Vector</A>
<LI><A NAME="tex2html92" HREF="node84.html#SECTION000471000000000000000">
SLA_DVXV - Vector Product</A>
<LI><A NAME="tex2html93" HREF="node85.html#SECTION000472000000000000000">
SLA_E2H - <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img65.gif"
ALT="$h,\delta$"> to Az,El</A>
<LI><A NAME="tex2html94" HREF="node86.html#SECTION000473000000000000000">
SLA_EARTH - Approx Earth Pos/Vel</A>
<LI><A NAME="tex2html95" HREF="node87.html#SECTION000474000000000000000">
SLA_ECLEQ - Ecliptic to Equatorial</A>
<LI><A NAME="tex2html96" HREF="node88.html#SECTION000475000000000000000">
SLA_ECMAT - Form <IMG WIDTH="81" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img95.gif"
ALT="$\alpha,\delta\rightarrow\lambda,\beta$"> Matrix</A>
<LI><A NAME="tex2html97" HREF="node89.html#SECTION000476000000000000000">
SLA_ECOR - RV & Time Corrns to Sun</A>
<LI><A NAME="tex2html98" HREF="node90.html#SECTION000477000000000000000">
SLA_EG50 - B1950 <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"> to Galactic</A>
<LI><A NAME="tex2html99" HREF="node91.html#SECTION000478000000000000000">
SLA_EL2UE - Conventional to Universal Elements</A>
<LI><A NAME="tex2html100" HREF="node92.html#SECTION000479000000000000000">
SLA_EPB - MJD to Besselian Epoch</A>
<LI><A NAME="tex2html101" HREF="node93.html#SECTION000480000000000000000">
SLA_EPB2D - Besselian Epoch to MJD</A>
<LI><A NAME="tex2html102" HREF="node94.html#SECTION000481000000000000000">
SLA_EPCO - Convert Epoch to B or J</A>
<LI><A NAME="tex2html103" HREF="node95.html#SECTION000482000000000000000">
SLA_EPJ - MJD to Julian Epoch</A>
<LI><A NAME="tex2html104" HREF="node96.html#SECTION000483000000000000000">
SLA_EPJ2D - Julian Epoch to MJD</A>
<LI><A NAME="tex2html105" HREF="node97.html#SECTION000484000000000000000">
SLA_EQECL - J2000 <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"> to Ecliptic</A>
<LI><A NAME="tex2html106" HREF="node98.html#SECTION000485000000000000000">
SLA_EQEQX - Equation of the Equinoxes</A>
<LI><A NAME="tex2html107" HREF="node99.html#SECTION000486000000000000000">
SLA_EQGAL - J2000 <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"> to Galactic</A>
<LI><A NAME="tex2html108" HREF="node100.html#SECTION000487000000000000000">
SLA_ETRMS - E-terms of Aberration</A>
<LI><A NAME="tex2html109" HREF="node101.html#SECTION000488000000000000000">
SLA_EULER - Rotation Matrix from Euler Angles</A>
<LI><A NAME="tex2html110" HREF="node102.html#SECTION000489000000000000000">
SLA_EVP - Earth Position & Velocity</A>
<LI><A NAME="tex2html111" HREF="node103.html#SECTION000490000000000000000">
SLA_FITXY - Fit Linear Model to Two <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
SRC="img20.gif"
ALT="$[\,x,y\,]$"> Sets</A>
<LI><A NAME="tex2html112" HREF="node104.html#SECTION000491000000000000000">
SLA_FK425 - FK4 to FK5</A>
<LI><A NAME="tex2html113" HREF="node105.html#SECTION000492000000000000000">
SLA_FK45Z - FK4 to FK5, no P.M. or Parallax</A>
<LI><A NAME="tex2html114" HREF="node106.html#SECTION000493000000000000000">
SLA_FK524 - FK5 to FK4</A>
<LI><A NAME="tex2html115" HREF="node107.html#SECTION000494000000000000000">
SLA_FK52H - FK5 to Hipparcos</A>
<LI><A NAME="tex2html116" HREF="node108.html#SECTION000495000000000000000">
SLA_FK54Z - FK5 to FK4, no P.M. or Parallax</A>
<LI><A NAME="tex2html117" HREF="node109.html#SECTION000496000000000000000">
SLA_FK5HZ - FK5 to Hipparcos, no P.M.</A>
<LI><A NAME="tex2html118" HREF="node110.html#SECTION000497000000000000000">
SLA_FLOTIN - Decode a Real Number</A>
<LI><A NAME="tex2html119" HREF="node111.html#SECTION000498000000000000000">
SLA_GALEQ - Galactic to J2000 <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"></A>
<LI><A NAME="tex2html120" HREF="node112.html#SECTION000499000000000000000">
SLA_GALSUP - Galactic to Supergalactic</A>
<LI><A NAME="tex2html121" HREF="node113.html#SECTION0004100000000000000000">
SLA_GE50 - Galactic to B1950 <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"></A>
<LI><A NAME="tex2html122" HREF="node114.html#SECTION0004101000000000000000">
SLA_GEOC - Geodetic to Geocentric</A>
<LI><A NAME="tex2html123" HREF="node115.html#SECTION0004102000000000000000">
SLA_GMST - UT to GMST</A>
<LI><A NAME="tex2html124" HREF="node116.html#SECTION0004103000000000000000">
SLA_GMSTA - UT to GMST (extra precision)</A>
<LI><A NAME="tex2html125" HREF="node117.html#SECTION0004104000000000000000">
SLA_GRESID - Gaussian Residual</A>
<LI><A NAME="tex2html126" HREF="node118.html#SECTION0004105000000000000000">
SLA_H2E - Az,El to <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img65.gif"
ALT="$h,\delta$"></A>
<LI><A NAME="tex2html127" HREF="node119.html#SECTION0004106000000000000000">
SLA_H2FK5 - Hipparcos to FK5</A>
<LI><A NAME="tex2html128" HREF="node120.html#SECTION0004107000000000000000">
SLA_HFK5Z - Hipparcos to FK5, no P.M.</A>
<LI><A NAME="tex2html129" HREF="node121.html#SECTION0004108000000000000000">
SLA_IMXV - Apply 3D Reverse Rotation</A>
<LI><A NAME="tex2html130" HREF="node122.html#SECTION0004109000000000000000">
SLA_INTIN - Decode an Integer Number</A>
<LI><A NAME="tex2html131" HREF="node123.html#SECTION0004110000000000000000">
SLA_INVF - Invert Linear Model</A>
<LI><A NAME="tex2html132" HREF="node124.html#SECTION0004111000000000000000">
SLA_KBJ - Select Epoch Prefix</A>
<LI><A NAME="tex2html133" HREF="node125.html#SECTION0004112000000000000000">
SLA_M2AV - Rotation Matrix to Axial Vector</A>
<LI><A NAME="tex2html134" HREF="node126.html#SECTION0004113000000000000000">
SLA_MAP - Mean to Apparent</A>
<LI><A NAME="tex2html135" HREF="node127.html#SECTION0004114000000000000000">
SLA_MAPPA - Mean to Apparent Parameters</A>
<LI><A NAME="tex2html136" HREF="node128.html#SECTION0004115000000000000000">
SLA_MAPQK - Quick Mean to Apparent</A>
<LI><A NAME="tex2html137" HREF="node129.html#SECTION0004116000000000000000">
SLA_MAPQKZ - Quick Mean-Appt, no PM <I>etc.</I></A>
<LI><A NAME="tex2html138" HREF="node130.html#SECTION0004117000000000000000">
SLA_MOON - Approx Moon Pos/Vel</A>
<LI><A NAME="tex2html139" HREF="node131.html#SECTION0004118000000000000000">
SLA_MXM - Multiply <IMG WIDTH="39" HEIGHT="25" ALIGN="MIDDLE" BORDER="0"
SRC="img18.gif"
ALT="$3\times3$"> Matrices</A>
<LI><A NAME="tex2html140" HREF="node132.html#SECTION0004119000000000000000">
SLA_MXV - Apply 3D Rotation</A>
<LI><A NAME="tex2html141" HREF="node133.html#SECTION0004120000000000000000">
SLA_NUT - Nutation Matrix</A>
<LI><A NAME="tex2html142" HREF="node134.html#SECTION0004121000000000000000">
SLA_NUTC - Nutation Components</A>
<LI><A NAME="tex2html143" HREF="node135.html#SECTION0004122000000000000000">
SLA_OAP - Observed to Apparent</A>
<LI><A NAME="tex2html144" HREF="node136.html#SECTION0004123000000000000000">
SLA_OAPQK - Quick Observed to Apparent</A>
<LI><A NAME="tex2html145" HREF="node137.html#SECTION0004124000000000000000">
SLA_OBS - Observatory Parameters</A>
<LI><A NAME="tex2html146" HREF="node138.html#SECTION0004125000000000000000">
SLA_PA - <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img65.gif"
ALT="$h,\delta$"> to Parallactic Angle</A>
<LI><A NAME="tex2html147" HREF="node139.html#SECTION0004126000000000000000">
SLA_PAV - Position-Angle Between Two Directions</A>
<LI><A NAME="tex2html148" HREF="node140.html#SECTION0004127000000000000000">
SLA_PCD - Apply Radial Distortion</A>
<LI><A NAME="tex2html149" HREF="node141.html#SECTION0004128000000000000000">
SLA_PDA2H - H.A. for a Given Azimuth</A>
<LI><A NAME="tex2html150" HREF="node142.html#SECTION0004129000000000000000">
SLA_PDQ2H - H.A. for a Given P.A.</A>
<LI><A NAME="tex2html151" HREF="node143.html#SECTION0004130000000000000000">
SLA_PERMUT - Next Permutation</A>
<LI><A NAME="tex2html152" HREF="node144.html#SECTION0004131000000000000000">
SLA_PERTEL - Perturbed Orbital Elements</A>
<LI><A NAME="tex2html153" HREF="node145.html#SECTION0004132000000000000000">
SLA_PERTUE - Perturbed Universal Elements</A>
<LI><A NAME="tex2html154" HREF="node146.html#SECTION0004133000000000000000">
SLA_PLANEL - Planet Position from Elements</A>
<LI><A NAME="tex2html155" HREF="node147.html#SECTION0004134000000000000000">
SLA_PLANET - Planetary Ephemerides</A>
<LI><A NAME="tex2html156" HREF="node148.html#SECTION0004135000000000000000">
SLA_PLANTE - <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
SRC="img3.gif"
ALT="$[\,\alpha,\delta\,]$"> of Planet from Elements</A>
<LI><A NAME="tex2html157" HREF="node149.html#SECTION0004136000000000000000">
SLA_PM - Proper Motion</A>
<LI><A NAME="tex2html158" HREF="node150.html#SECTION0004137000000000000000">
SLA_POLMO - Polar Motion</A>
<LI><A NAME="tex2html159" HREF="node151.html#SECTION0004138000000000000000">
SLA_PREBN - Precession Matrix (FK4)</A>
<LI><A NAME="tex2html160" HREF="node152.html#SECTION0004139000000000000000">
SLA_PREC - Precession Matrix (FK5)</A>
<LI><A NAME="tex2html161" HREF="node153.html#SECTION0004140000000000000000">
SLA_PRECES - Precession</A>
<LI><A NAME="tex2html162" HREF="node154.html#SECTION0004141000000000000000">
SLA_PRECL - Precession Matrix (latest)</A>
<LI><A NAME="tex2html163" HREF="node155.html#SECTION0004142000000000000000">
SLA_PRENUT - Precession/Nutation Matrix</A>
<LI><A NAME="tex2html164" HREF="node156.html#SECTION0004143000000000000000">
SLA_PV2EL - Orbital Elements from Position/Velocity</A>
<LI><A NAME="tex2html165" HREF="node157.html#SECTION0004144000000000000000">
SLA_PV2UE - Position/Velocity to Universal Elements</A>
<LI><A NAME="tex2html166" HREF="node158.html#SECTION0004145000000000000000">
SLA_PVOBS - Observatory Position & Velocity</A>
<LI><A NAME="tex2html167" HREF="node159.html#SECTION0004146000000000000000">
SLA_PXY - Apply Linear Model</A>
<LI><A NAME="tex2html168" HREF="node160.html#SECTION0004147000000000000000">
SLA_RANDOM - Random Number</A>
<LI><A NAME="tex2html169" HREF="node161.html#SECTION0004148000000000000000">
SLA_RANGE - Put Angle into Range <IMG WIDTH="25" HEIGHT="25" ALIGN="MIDDLE" BORDER="0"
SRC="img47.gif"
ALT="$\pm \pi$"></A>
<LI><A NAME="tex2html170" HREF="node162.html#SECTION0004149000000000000000">
SLA_RANORM - Put Angle into Range <IMG WIDTH="43" HEIGHT="25" ALIGN="MIDDLE" BORDER="0"
SRC="img66.gif"
ALT="$0\!-\!2\pi$"></A>
<LI><A NAME="tex2html171" HREF="node163.html#SECTION0004150000000000000000">
SLA_RCC - Barycentric Coordinate Time</A>
<LI><A NAME="tex2html172" HREF="node164.html#SECTION0004151000000000000000">
SLA_RDPLAN - Apparent <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
SRC="img3.gif"
ALT="$[\,\alpha,\delta\,]$"> of Planet</A>
<LI><A NAME="tex2html173" HREF="node165.html#SECTION0004152000000000000000">
SLA_REFCO - Refraction Constants</A>
<LI><A NAME="tex2html174" HREF="node166.html#SECTION0004153000000000000000">
SLA_REFCOQ - Refraction Constants (fast)</A>
<LI><A NAME="tex2html175" HREF="node167.html#SECTION0004154000000000000000">
SLA_REFRO - Refraction</A>
<LI><A NAME="tex2html176" HREF="node168.html#SECTION0004155000000000000000">
SLA_REFV - Apply Refraction to Vector</A>
<LI><A NAME="tex2html177" HREF="node169.html#SECTION0004156000000000000000">
SLA_REFZ - Apply Refraction to ZD</A>
<LI><A NAME="tex2html178" HREF="node170.html#SECTION0004157000000000000000">
SLA_RVEROT - RV Corrn to Earth Centre</A>
<LI><A NAME="tex2html179" HREF="node171.html#SECTION0004158000000000000000">
SLA_RVGALC - RV Corrn to Galactic Centre</A>
<LI><A NAME="tex2html180" HREF="node172.html#SECTION0004159000000000000000">
SLA_RVLG - RV Corrn to Local Group</A>
<LI><A NAME="tex2html181" HREF="node173.html#SECTION0004160000000000000000">
SLA_RVLSRD - RV Corrn to Dynamical LSR</A>
<LI><A NAME="tex2html182" HREF="node174.html#SECTION0004161000000000000000">
SLA_RVLSRK - RV Corrn to Kinematical LSR</A>
<LI><A NAME="tex2html183" HREF="node175.html#SECTION0004162000000000000000">
SLA_S2TP - Spherical to Tangent Plane</A>
<LI><A NAME="tex2html184" HREF="node176.html#SECTION0004163000000000000000">
SLA_SEP - Angle Between 2 Points on Sphere</A>
<LI><A NAME="tex2html185" HREF="node177.html#SECTION0004164000000000000000">
SLA_SMAT - Solve Simultaneous Equations</A>
<LI><A NAME="tex2html186" HREF="node178.html#SECTION0004165000000000000000">
SLA_SUBET - Remove E-terms</A>
<LI><A NAME="tex2html187" HREF="node179.html#SECTION0004166000000000000000">
SLA_SUPGAL - Supergalactic to Galactic</A>
<LI><A NAME="tex2html188" HREF="node180.html#SECTION0004167000000000000000">
SLA_SVD - Singular Value Decomposition</A>
<LI><A NAME="tex2html189" HREF="node181.html#SECTION0004168000000000000000">
SLA_SVDCOV - Covariance Matrix from SVD</A>
<LI><A NAME="tex2html190" HREF="node182.html#SECTION0004169000000000000000">
SLA_SVDSOL - Solution Vector from SVD</A>
<LI><A NAME="tex2html191" HREF="node183.html#SECTION0004170000000000000000">
SLA_TP2S - Tangent Plane to Spherical</A>
<LI><A NAME="tex2html192" HREF="node184.html#SECTION0004171000000000000000">
SLA_TP2V - Tangent Plane to Direction Cosines</A>
<LI><A NAME="tex2html193" HREF="node185.html#SECTION0004172000000000000000">
SLA_TPS2C - Plate centre from <IMG WIDTH="26" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img90.gif"
ALT="$\xi,\eta$"> and <IMG WIDTH="28" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img91.gif"
ALT="$\alpha,\delta$"></A>
<LI><A NAME="tex2html194" HREF="node186.html#SECTION0004173000000000000000">
SLA_TPV2C - Plate centre from <IMG WIDTH="26" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img90.gif"
ALT="$\xi,\eta$"> and <I>x</I>,<I>y</I>,<I>z</I></A>
<LI><A NAME="tex2html195" HREF="node187.html#SECTION0004174000000000000000">
SLA_UE2EL - Universal to Conventional Elements</A>
<LI><A NAME="tex2html196" HREF="node188.html#SECTION0004175000000000000000">
SLA_UE2PV - Pos/Vel from Universal Elements</A>
<LI><A NAME="tex2html197" HREF="node189.html#SECTION0004176000000000000000">
SLA_UNPCD - Remove Radial Distortion</A>
<LI><A NAME="tex2html198" HREF="node190.html#SECTION0004177000000000000000">
SLA_V2TP - Direction Cosines to Tangent Plane</A>
<LI><A NAME="tex2html199" HREF="node191.html#SECTION0004178000000000000000">
SLA_VDV - Scalar Product</A>
<LI><A NAME="tex2html200" HREF="node192.html#SECTION0004179000000000000000">
SLA_VN - Normalize Vector</A>
<LI><A NAME="tex2html201" HREF="node193.html#SECTION0004180000000000000000">
SLA_VXV - Vector Product</A>
<LI><A NAME="tex2html202" HREF="node194.html#SECTION0004181000000000000000">
SLA_WAIT - Time Delay</A>
<LI><A NAME="tex2html203" HREF="node195.html#SECTION0004182000000000000000">
SLA_XY2XY - Apply Linear Model to an <IMG WIDTH="42" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
SRC="img20.gif"
ALT="$[\,x,y\,]$"></A>
<LI><A NAME="tex2html204" HREF="node196.html#SECTION0004183000000000000000">
SLA_ZD - <IMG WIDTH="27" HEIGHT="27" ALIGN="MIDDLE" BORDER="0"
SRC="img65.gif"
ALT="$h,\delta$"> to Zenith Distance</A>
</UL>
<LI><A NAME="tex2html205" HREF="node197.html#SECTION00050000000000000000">
EXPLANATION AND EXAMPLES</A>
<UL>
<LI><A NAME="tex2html206" HREF="node198.html#SECTION00051000000000000000">
Spherical Trigonometry</A>
<UL>
<LI><A NAME="tex2html207" HREF="node199.html#SECTION00051100000000000000">
Formatting angles</A>
</UL>
<LI><A NAME="tex2html208" HREF="node200.html#SECTION00052000000000000000">
Vectors and Matrices</A>
<UL>
<LI><A NAME="tex2html209" HREF="node201.html#SECTION00052100000000000000">
Using vectors</A>
</UL>
<LI><A NAME="tex2html210" HREF="node202.html#SECTION00053000000000000000">
Celestial Coordinate Systems</A>
<LI><A NAME="tex2html211" HREF="node203.html#SECTION00054000000000000000">
Precession and Nutation</A>
<UL>
<LI><A NAME="tex2html212" HREF="node204.html#SECTION00054100000000000000">
SLALIB support for precession and nutation</A>
</UL>
<LI><A NAME="tex2html213" HREF="node205.html#SECTION00055000000000000000">
Mean Places</A>
<LI><A NAME="tex2html214" HREF="node206.html#SECTION00056000000000000000">
Epoch</A>
<LI><A NAME="tex2html215" HREF="node207.html#SECTION00057000000000000000">
Proper Motion</A>
<LI><A NAME="tex2html216" HREF="node208.html#SECTION00058000000000000000">
Parallax and Radial Velocity</A>
<LI><A NAME="tex2html217" HREF="node209.html#SECTION00059000000000000000">
Aberration</A>
<LI><A NAME="tex2html218" HREF="node210.html#SECTION000510000000000000000">
Different Sorts of Mean Place</A>
<LI><A NAME="tex2html219" HREF="node211.html#SECTION000511000000000000000">
Mean Place Transformations</A>
<LI><A NAME="tex2html220" HREF="node212.html#SECTION000512000000000000000">
Mean Place to Apparent Place</A>
<LI><A NAME="tex2html221" HREF="node213.html#SECTION000513000000000000000">
Apparent Place to Observed Place</A>
<UL>
<LI><A NAME="tex2html222" HREF="node214.html#SECTION000513100000000000000">
Refraction</A>
<LI><A NAME="tex2html223" HREF="node215.html#SECTION000513200000000000000">
Efficiency considerations</A>
</UL>
<LI><A NAME="tex2html224" HREF="node216.html#SECTION000514000000000000000">
The Hipparcos Catalogue and the ICRS</A>
<LI><A NAME="tex2html225" HREF="node217.html#SECTION000515000000000000000">
Timescales</A>
<UL>
<LI><A NAME="tex2html226" HREF="node218.html#SECTION000515100000000000000">
Atomic Time: TAI</A>
<LI><A NAME="tex2html227" HREF="node219.html#SECTION000515200000000000000">
Universal Time: UTC, UT1</A>
<LI><A NAME="tex2html228" HREF="node220.html#SECTION000515300000000000000">
Sidereal Time: GMST, LAST</A>
<LI><A NAME="tex2html229" HREF="node221.html#SECTION000515400000000000000">
Dynamical Time: TT, TDB</A>
</UL>
<LI><A NAME="tex2html230" HREF="node222.html#SECTION000516000000000000000">
Calendars</A>
<LI><A NAME="tex2html231" HREF="node223.html#SECTION000517000000000000000">
Geocentric Coordinates</A>
<LI><A NAME="tex2html232" HREF="node224.html#SECTION000518000000000000000">
Ephemerides</A>
<LI><A NAME="tex2html233" HREF="node225.html#SECTION000519000000000000000">
Radial Velocity and Light-Time Corrections</A>
<LI><A NAME="tex2html234" HREF="node226.html#SECTION000520000000000000000">
Focal-Plane Astrometry</A>
<LI><A NAME="tex2html235" HREF="node227.html#SECTION000521000000000000000">
Numerical Methods</A>
</UL>
<LI><A NAME="tex2html236" HREF="node228.html#SECTION00060000000000000000">
SUMMARY OF CALLS</A>
<LI><A NAME="tex2html237" HREF="node229.html#SECTION00070000000000000000">
About this document ... </A>
</UL>
<!--End of Table of Child-Links-->
<BR> <HR>
<A NAME="tex2html7" HREF="node1.html">
<IMG WIDTH="37" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="next" SRC="next_motif.gif"></A>
<IMG WIDTH="26" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="up" SRC="up_motif_gr.gif">
<IMG WIDTH="63" HEIGHT="24" ALIGN="BOTTOM" BORDER="0" ALT="previous" SRC="previous_motif_gr.gif"> <A HREF="sun67.html#stardoccontents"><IMG ALIGN="BOTTOM" BORDER="0"
SRC="contents_motif.gif"></A>
<BR>
<B> Next:</B> <A NAME="tex2html8" HREF="node1.html">Abstract</A>
<BR>
<BR> <HR> <P>
<P><!--End of Navigation Panel-->
<ADDRESS>
<I>SLALIB --- Positional Astronomy Library<BR>Starlink User Note 67<BR>P. T. Wallace<BR>12 October 1999<BR>E-mail:ptw@star.rl.ac.uk</I>
</ADDRESS>
</BODY>
</HTML>
|
