1 /* Copyright 2002-2021 CS GROUP
2 * Licensed to CS GROUP (CS) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * CS licenses this file to You under the Apache License, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 */
17 package org.orekit.frames;
18
19 import java.io.BufferedReader;
20 import java.io.IOException;
21 import java.io.InputStream;
22 import java.io.InputStreamReader;
23 import java.nio.charset.StandardCharsets;
24 import java.util.ArrayList;
25 import java.util.Arrays;
26 import java.util.HashMap;
27 import java.util.List;
28 import java.util.Map;
29 import java.util.SortedSet;
30 import java.util.function.Supplier;
31 import java.util.regex.Matcher;
32 import java.util.regex.Pattern;
33
34 import org.hipparchus.util.FastMath;
35 import org.orekit.data.DataLoader;
36 import org.orekit.data.DataProvidersManager;
37 import org.orekit.errors.OrekitException;
38 import org.orekit.errors.OrekitInternalError;
39 import org.orekit.errors.OrekitMessages;
40 import org.orekit.time.AbsoluteDate;
41 import org.orekit.time.DateComponents;
42 import org.orekit.time.TimeScale;
43 import org.orekit.utils.IERSConventions;
44 import org.orekit.utils.units.UnitsConverter;
45
46 /** Loader for bulletin A files.
47 * <p>Bulletin A files contain {@link EOPEntry
48 * Earth Orientation Parameters} for a few days periods, they
49 * correspond to rapid data estimations, suitable for near-real time
50 * and prediction purposes. Prediction series are only available for
51 * pole motion xp, yp and UT1-UTC, they are not available for
52 * pole offsets (Δδψ/Δδε and x/y).</p>
53 * <p>A bulletin A published on Modified Julian Day mjd (nominally a
54 * Thursday) will generally contain:
55 * </p>
56 * <ul>
57 * <li>rapid service xp, yp and UT1-UTC data from mjd-6 to mjd</li>
58 * <li>prediction xp, yp and UT1-UTC data from mjd+1 to mjd+365</li>
59 * <li>if it is first bulletin of month m, final values xp, yp and
60 * UT1-UTC data from day 2 of month m-2 to day 1 of month m-1</li>
61 * <li>rapid service pole offsets Δδψ/Δδε and x/y if available, for some
62 * varying period somewhere from mjd-30 to mjd-10 (see below)</li>
63 * <li>if it is first bulletin of month m, final values pole offsets
64 * Δδψ/Δδε and x/y data from day 2 of month m-2 to day 1 of month
65 * m-1</li>
66 * </ul>
67 * <p>
68 * There are some discrepancies in the rapid service time range above,
69 * mainly when the nominal publication Thursday corresponds to holidays.
70 * In this case a bulletin may be published the day before and have a 6
71 * days span only for rapid data, and a later bulletin will have an 8 days
72 * span to recover the normal schedule. This occurred for bulletin A Vol.
73 * XVIII No. 047, bulletin A Vol. XVIII No. 048, bulletin A Vol. XXI No.
74 * 052 and bulletin A Vol. XXII No. 001.
75 * </p>
76 * <p>Rapid service for pole offsets appears irregular. As extreme examples
77 * bulletin A Vol. XXVI No. 037 from 2013-09-12 contained 15 entries
78 * for pole offsets, from mjd-22 to mjd-8, bulletin A Vol. XXVI No. 039
79 * from 2013-09-26 contained only 3 entries for pole offsets, from mjd-15
80 * to mjd-13, and bulletin A Vol. XXVI No. 040 from 2013-10-03 contained no
81 * rapid service pole offsets at all, it contained only final values. Despite
82 * this irregularity, rapid service data is continuous over consecutive files,
83 * so the mean number of entries is 7 as the files are published on a weekly
84 * basis.
85 * </p>
86 * <p>
87 * There are no prediction data for pole offsets.
88 * </p>
89 * <p>
90 * This loader reads both the rapid service, the prediction and the final
91 * values parts. As successive files have overlaps between all these sections,
92 * values extracted from latest files (with respect to the covered dates)
93 * override values extracted from earlier files, regardless of the files
94 * reading order. If numerous bulletins A covering more than one year are read,
95 * one particular date will typically appear in the prediction section of
96 * 52 or 53 files, then in the rapid data section of one file, then it will
97 * be missing in a few files, and will finally appear a last time in the
98 * final values sections of a last file. In this case, the value retained
99 * will be the one extracted from the final values section in the more
100 * recent file.
101 * </p>
102 * <p>
103 * If only one bulletin A file is read and it correspond to the first bulletin
104 * of a month, it will have a roughly one month wide hole between the
105 * final data and the rapid data. This hole will trigger an error as EOP
106 * continuity is checked by default for at most 5 days holes. In this case,
107 * users should call something like {@link Frames#setEOPContinuityThreshold(double)
108 * FramesFactory.setEOPContinuityThreshold(Constants.JULIAN_YEAR)} to prevent
109 * the error to be triggered.
110 * </p>
111 * <p>The bulletin A files are recognized thanks to their base names,
112 * which must match the pattern <code>bulletina-xxxx-###.txt</code>,
113 * (or the same ending with <code>.gz</code> for gzip-compressed files)
114 * where x stands for a roman numeral character and # stands for a digit
115 * character.</p>
116 * <p>
117 * This class is immutable and hence thread-safe
118 * </p>
119 * @author Luc Maisonobe
120 * @since 7.0
121 */
122 class BulletinAFilesLoader extends AbstractEopLoader implements EOPHistoryLoader {
123
124 /** Regular expression matching blanks at start of line. */
125 private static final String LINE_START_REGEXP = "^\\p{Blank}+";
126
127 /** Regular expression matching blanks at end of line. */
128 private static final String LINE_END_REGEXP = "\\p{Blank}*$";
129
130 /** Regular expression matching integers. */
131 private static final String INTEGER_REGEXP = "[-+]?\\p{Digit}+";
132
133 /** Regular expression matching real numbers. */
134 private static final String REAL_REGEXP = "[-+]?(?:(?:\\p{Digit}+(?:\\.\\p{Digit}*)?)|(?:\\.\\p{Digit}+))(?:[eE][-+]?\\p{Digit}+)?";
135
136 /** Regular expression matching an integer field to store. */
137 private static final String STORED_INTEGER_FIELD = "\\p{Blank}*(" + INTEGER_REGEXP + ")";
138
139 /** regular expression matching a Modified Julian Day field to store. */
140 private static final String STORED_MJD_FIELD = "\\p{Blank}+(\\p{Digit}\\p{Digit}\\p{Digit}\\p{Digit}\\p{Digit})";
141
142 /** Regular expression matching a real field to store. */
143 private static final String STORED_REAL_FIELD = "\\p{Blank}+(" + REAL_REGEXP + ")";
144
145 /** Regular expression matching a real field to ignore. */
146 private static final String IGNORED_REAL_FIELD = "\\p{Blank}+" + REAL_REGEXP;
147
148 /** Enum for files sections, in expected order.
149 * <p>The bulletin A weekly data files contain several sections,
150 * each introduced with some fixed header text and followed by tabular data.
151 * </p>
152 */
153 private enum Section {
154
155 /** Earth Orientation Parameters rapid service. */
156 // section 2 always contain rapid service data including error fields
157 // COMBINED EARTH ORIENTATION PARAMETERS:
158 //
159 // IERS Rapid Service
160 // MJD x error y error UT1-UTC error
161 // " " " " s s
162 // 13 8 30 56534 0.16762 .00009 0.32705 .00009 0.038697 0.000019
163 // 13 8 31 56535 0.16669 .00010 0.32564 .00010 0.038471 0.000019
164 // 13 9 1 56536 0.16592 .00009 0.32410 .00010 0.038206 0.000024
165 // 13 9 2 56537 0.16557 .00009 0.32270 .00009 0.037834 0.000024
166 // 13 9 3 56538 0.16532 .00009 0.32147 .00010 0.037351 0.000024
167 // 13 9 4 56539 0.16488 .00009 0.32044 .00010 0.036756 0.000023
168 // 13 9 5 56540 0.16435 .00009 0.31948 .00009 0.036036 0.000024
169 EOP_RAPID_SERVICE("^ *COMBINED EARTH ORIENTATION PARAMETERS: *$",
170 LINE_START_REGEXP +
171 STORED_INTEGER_FIELD + STORED_INTEGER_FIELD + STORED_INTEGER_FIELD +
172 STORED_MJD_FIELD +
173 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
174 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
175 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
176 LINE_END_REGEXP),
177
178 /** Earth Orientation Parameters final values. */
179 // the first bulletin A of each month also includes final values for the
180 // period covering from day 2 of month m-2 to day 1 of month m-1.
181 // IERS Final Values
182 // MJD x y UT1-UTC
183 // " " s
184 // 13 7 2 56475 0.1441 0.3901 0.05717
185 // 13 7 3 56476 0.1457 0.3895 0.05716
186 // 13 7 4 56477 0.1467 0.3887 0.05728
187 // 13 7 5 56478 0.1477 0.3875 0.05755
188 // 13 7 6 56479 0.1490 0.3862 0.05793
189 // 13 7 7 56480 0.1504 0.3849 0.05832
190 // 13 7 8 56481 0.1516 0.3835 0.05858
191 // 13 7 9 56482 0.1530 0.3822 0.05877
192 EOP_FINAL_VALUES("^ *IERS Final Values *$",
193 LINE_START_REGEXP +
194 STORED_INTEGER_FIELD + STORED_INTEGER_FIELD + STORED_INTEGER_FIELD +
195 STORED_MJD_FIELD +
196 STORED_REAL_FIELD +
197 STORED_REAL_FIELD +
198 STORED_REAL_FIELD +
199 LINE_END_REGEXP),
200
201 /** Earth Orientation Parameters prediction. */
202 // section 3 always contain prediction data without error fields
203 //
204 // PREDICTIONS:
205 // The following formulas will not reproduce the predictions given below,
206 // but may be used to extend the predictions beyond the end of this table.
207 //
208 // x = 0.0969 + 0.1110 cos A - 0.0103 sin A - 0.0435 cos C - 0.0171 sin C
209 // y = 0.3457 - 0.0061 cos A - 0.1001 sin A - 0.0171 cos C + 0.0435 sin C
210 // UT1-UTC = -0.0052 - 0.00104 (MJD - 56548) - (UT2-UT1)
211 //
212 // where A = 2*pi*(MJD-56540)/365.25 and C = 2*pi*(MJD-56540)/435.
213 //
214 // TAI-UTC(MJD 56541) = 35.0
215 // The accuracy may be estimated from the expressions:
216 // S x,y = 0.00068 (MJD-56540)**0.80 S t = 0.00025 (MJD-56540)**0.75
217 // Estimated accuracies are: Predictions 10 d 20 d 30 d 40 d
218 // Polar coord's 0.004 0.007 0.010 0.013
219 // UT1-UTC 0.0014 0.0024 0.0032 0.0040
220 //
221 // MJD x(arcsec) y(arcsec) UT1-UTC(sec)
222 // 2013 9 6 56541 0.1638 0.3185 0.03517
223 // 2013 9 7 56542 0.1633 0.3175 0.03420
224 // 2013 9 8 56543 0.1628 0.3164 0.03322
225 // 2013 9 9 56544 0.1623 0.3153 0.03229
226 // 2013 9 10 56545 0.1618 0.3142 0.03144
227 // 2013 9 11 56546 0.1612 0.3131 0.03071
228 // 2013 9 12 56547 0.1607 0.3119 0.03008
229 EOP_PREDICTION("^ *PREDICTIONS: *$",
230 LINE_START_REGEXP +
231 STORED_INTEGER_FIELD + STORED_INTEGER_FIELD + STORED_INTEGER_FIELD +
232 STORED_MJD_FIELD +
233 STORED_REAL_FIELD +
234 STORED_REAL_FIELD +
235 STORED_REAL_FIELD +
236 LINE_END_REGEXP),
237
238 /** Pole offsets, IAU-1980. */
239 // section 4 may contain rapid service pole offset series including error fields
240 // CELESTIAL POLE OFFSET SERIES:
241 // NEOS Celestial Pole Offset Series
242 // MJD dpsi error deps error
243 // (msec. of arc)
244 // 56519 -87.47 0.13 -12.96 0.08
245 // 56520 -87.72 0.13 -13.20 0.08
246 // 56521 -87.79 0.19 -13.56 0.11
247 POLE_OFFSETS_IAU_1980_RAPID_SERVICE("^ *NEOS Celestial Pole Offset Series *$",
248 LINE_START_REGEXP +
249 STORED_MJD_FIELD +
250 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
251 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
252 LINE_END_REGEXP),
253
254 /** Pole offsets, IAU-1980 final values. */
255 // the format for the IAU-2000 series is similar, but the meanings of the fields
256 // are different
257 // IAU2000A Celestial Pole Offset Series
258 // MJD dX error dY error
259 // (msec. of arc)
260 // 56519 -0.246 0.052 -0.223 0.080
261 // 56520 -0.239 0.052 -0.248 0.080
262 // 56521 -0.224 0.076 -0.277 0.110
263 POLE_OFFSETS_IAU_1980_FINAL_VALUES("^ *IERS Celestial Pole Offset Final Series *$",
264 LINE_START_REGEXP +
265 STORED_MJD_FIELD +
266 STORED_REAL_FIELD +
267 STORED_REAL_FIELD +
268 LINE_END_REGEXP),
269
270 /** Pole offsets, IAU-2000. */
271 // the first bulletin A of each month also includes final values for the
272 // period covering from day 2 of month m-2 to day 1 of month m-1.
273 // IERS Celestial Pole Offset Final Series
274 // MJD dpsi deps
275 // (msec. of arc)
276 // 56475 -81.0 -13.3
277 // 56476 -81.2 -13.4
278 // 56477 -81.6 -13.4
279 // 56478 -82.2 -13.5
280 // 56479 -82.5 -13.6
281 // 56480 -82.5 -13.7
282 POLE_OFFSETS_IAU_2000_RAPID_SERVICE("^ *IAU2000A Celestial Pole Offset Series *$",
283 LINE_START_REGEXP +
284 STORED_MJD_FIELD +
285 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
286 STORED_REAL_FIELD + IGNORED_REAL_FIELD +
287 LINE_END_REGEXP),
288
289 /** Pole offsets, IAU-2000 final values. */
290 // the format for the IAU-2000 series is similar, but the meanings of the fields
291 // are different
292 // IAU2000A Celestial Pole Offset Final Series
293 // MJD dX dY
294 // (msec. of arc)
295 // 56475 0.00 -0.28
296 // 56476 -0.06 -0.29
297 // 56477 -0.07 -0.27
298 // 56478 -0.12 -0.33
299 // 56479 -0.12 -0.33
300 // 56480 -0.13 -0.36
301 POLE_OFFSETS_IAU_2000_FINAL_VALUES("^ *IAU2000A Celestial Pole Offset Final Series *$",
302 LINE_START_REGEXP +
303 STORED_MJD_FIELD +
304 STORED_REAL_FIELD +
305 STORED_REAL_FIELD +
306 LINE_END_REGEXP);
307
308 /** Header pattern. */
309 private final Pattern header;
310
311 /** Data pattern. */
312 private final Pattern data;
313
314 /** Simple constructor.
315 * @param headerRegExp regular expression for header
316 * @param dataRegExp regular expression for data
317 */
318 Section(final String headerRegExp, final String dataRegExp) {
319 this.header = Pattern.compile(headerRegExp);
320 this.data = Pattern.compile(dataRegExp);
321 }
322
323 /** Check if a line matches the section header.
324 * @param line line to check
325 * @return true if the line matches the header
326 */
327 public boolean matchesHeader(final String line) {
328 return header.matcher(line).matches();
329 }
330
331 /** Get the data fields from a line.
332 * @param line line to parse
333 * @return extracted fields, or null if line does not match data format
334 */
335 public String[] getFields(final String line) {
336 final Matcher matcher = data.matcher(line);
337 if (matcher.matches()) {
338 final String[] fields = new String[matcher.groupCount()];
339 for (int i = 0; i < fields.length; ++i) {
340 fields[i] = matcher.group(i + 1);
341 }
342 return fields;
343 } else {
344 return null;
345 }
346 }
347
348 }
349
350 /** Build a loader for IERS bulletins A files.
351 * @param supportedNames regular expression for supported files names
352 * @param manager provides access to the bulletin A files.
353 * @param utcSupplier UTC time scale.
354 */
355 BulletinAFilesLoader(final String supportedNames,
356 final DataProvidersManager manager,
357 final Supplier<TimeScale> utcSupplier) {
358 super(supportedNames, manager, utcSupplier);
359 }
360
361 /** {@inheritDoc} */
362 public void fillHistory(final IERSConventions.NutationCorrectionConverter converter,
363 final SortedSet<EOPEntry> history) {
364 final Parser parser = new Parser();
365 this.feed(parser);
366 parser.fill(history);
367 }
368
369 /** Internal class performing the parsing. */
370 private class Parser implements DataLoader {
371
372 /** Map for xp, yp, dut1 fields read in different sections. */
373 private final Map<Integer, double[]> eopFieldsMap;
374
375 /** Map for pole offsets fields read in different sections. */
376 private final Map<Integer, double[]> poleOffsetsFieldsMap;
377
378 /** Configuration for ITRF versions. */
379 private final ItrfVersionProvider itrfVersionProvider;
380
381 /** ITRF version configuration. */
382 private ITRFVersionLoader.ITRFVersionConfiguration configuration;
383
384 /** File name. */
385 private String fileName;
386
387 /** Current line number. */
388 private int lineNumber;
389
390 /** Current line. */
391 private String line;
392
393 /** Earliest parsed data. */
394 private int mjdMin;
395
396 /** Latest parsed data. */
397 private int mjdMax;
398
399 /** First MJD parsed in current file. */
400 private int firstMJD;
401
402 /** Simple constructor.
403 */
404 Parser() {
405 this.eopFieldsMap = new HashMap<>();
406 this.poleOffsetsFieldsMap = new HashMap<>();
407 this.itrfVersionProvider = new ITRFVersionLoader(
408 ITRFVersionLoader.SUPPORTED_NAMES,
409 getDataProvidersManager());
410 this.lineNumber = 0;
411 this.mjdMin = Integer.MAX_VALUE;
412 this.mjdMax = Integer.MIN_VALUE;
413 this.firstMJD = -1;
414 }
415
416 /** {@inheritDoc} */
417 public boolean stillAcceptsData() {
418 return true;
419 }
420
421 /** {@inheritDoc} */
422 public void loadData(final InputStream input, final String name)
423 throws IOException {
424
425 this.configuration = null;
426 this.fileName = name;
427
428 // set up a reader for line-oriented bulletin A files
429 try (BufferedReader reader = new BufferedReader(new InputStreamReader(input, StandardCharsets.UTF_8))) {
430 lineNumber = 0;
431 firstMJD = -1;
432
433 // loop over sections
434 final List<Section> remaining = new ArrayList<>(Arrays.asList(Section.values()));
435 for (Section section = nextSection(remaining, reader);
436 section != null;
437 section = nextSection(remaining, reader)) {
438
439 switch (section) {
440 case EOP_RAPID_SERVICE :
441 case EOP_FINAL_VALUES :
442 case EOP_PREDICTION :
443 loadXYDT(section, reader, name);
444 break;
445 case POLE_OFFSETS_IAU_1980_RAPID_SERVICE :
446 case POLE_OFFSETS_IAU_1980_FINAL_VALUES :
447 loadPoleOffsets(section, false, reader, name);
448 break;
449 case POLE_OFFSETS_IAU_2000_RAPID_SERVICE :
450 case POLE_OFFSETS_IAU_2000_FINAL_VALUES :
451 loadPoleOffsets(section, true, reader, name);
452 break;
453 default :
454 // this should never happen
455 throw new OrekitInternalError(null);
456 }
457
458 // remove the already parsed section from the list
459 remaining.remove(section);
460
461 }
462
463 // check that the mandatory sections have been parsed
464 if (remaining.contains(Section.EOP_RAPID_SERVICE) ||
465 remaining.contains(Section.EOP_PREDICTION) ||
466 (remaining.contains(Section.POLE_OFFSETS_IAU_1980_RAPID_SERVICE) ^
467 remaining.contains(Section.POLE_OFFSETS_IAU_2000_RAPID_SERVICE)) ||
468 (remaining.contains(Section.POLE_OFFSETS_IAU_1980_FINAL_VALUES) ^
469 remaining.contains(Section.POLE_OFFSETS_IAU_2000_FINAL_VALUES))) {
470 throw new OrekitException(OrekitMessages.NOT_A_SUPPORTED_IERS_DATA_FILE, name);
471 }
472
473 }
474 }
475
476 /** Fill EOP history obtained after reading several files.
477 * @param history history to fill up
478 */
479 public void fill(final SortedSet<EOPEntry> history) {
480
481 double[] currentEOP = null;
482 double[] nextEOP = eopFieldsMap.get(mjdMin);
483 for (int mjd = mjdMin; mjd <= mjdMax; ++mjd) {
484
485 final AbsoluteDate mjdDate = AbsoluteDate.createMJDDate(mjd, 0, getUtc());
486 final double[] currentPole = poleOffsetsFieldsMap.get(mjd);
487
488 final double[] previousEOP = currentEOP;
489 currentEOP = nextEOP;
490 nextEOP = eopFieldsMap.get(mjd + 1);
491
492 if (currentEOP == null) {
493 if (currentPole != null) {
494 // we have only pole offsets for this date
495 if (configuration == null || !configuration.isValid(mjd)) {
496 // get a configuration for current name and date range
497 configuration = itrfVersionProvider.getConfiguration(fileName, mjd);
498 }
499 history.add(new EOPEntry(mjd,
500 0.0, 0.0, 0.0, 0.0,
501 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[1]),
502 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[2]),
503 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[3]),
504 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[4]),
505 configuration.getVersion(),
506 mjdDate));
507 }
508 } else {
509
510 // compute LOD as the opposite of the time derivative of UT1-UTC
511 final double lod;
512 if (previousEOP == null) {
513 if (nextEOP == null) {
514 // isolated point
515 lod = 0;
516 } else {
517 // first entry, we use a forward difference
518 lod = currentEOP[3] - nextEOP[3];
519 }
520 } else {
521 if (nextEOP == null) {
522 // last entry, we use a backward difference
523 lod = previousEOP[3] - currentEOP[3];
524 } else {
525 // regular entry, we use a centered difference
526 lod = 0.5 * (previousEOP[3] - nextEOP[3]);
527 }
528 }
529
530 if (configuration == null || !configuration.isValid(mjd)) {
531 // get a configuration for current name and date range
532 configuration = itrfVersionProvider.getConfiguration(fileName, mjd);
533 }
534 if (currentPole == null) {
535 // we have only EOP for this date
536 history.add(new EOPEntry(mjd,
537 currentEOP[3], lod,
538 UnitsConverter.ARC_SECONDS_TO_RADIANS.convert(currentEOP[1]),
539 UnitsConverter.ARC_SECONDS_TO_RADIANS.convert(currentEOP[2]),
540 0.0, 0.0, 0.0, 0.0,
541 configuration.getVersion(),
542 mjdDate));
543 } else {
544 // we have complete data
545 history.add(new EOPEntry(mjd,
546 currentEOP[3], lod,
547 UnitsConverter.ARC_SECONDS_TO_RADIANS.convert(currentEOP[1] ),
548 UnitsConverter.ARC_SECONDS_TO_RADIANS.convert(currentEOP[2] ),
549 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[1]),
550 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[2]),
551 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[3]),
552 UnitsConverter.MILLI_ARC_SECONDS_TO_RADIANS.convert(currentPole[4]),
553 configuration.getVersion(),
554 mjdDate));
555 }
556 }
557
558 }
559
560 }
561
562 /** Skip to next section header.
563 * @param sections sections to check for
564 * @param reader reader from where file content is obtained
565 * @return the next section or null if no section is found until end of file
566 * @exception IOException if data can't be read
567 */
568 private Section nextSection(final List<Section> sections,
569 final BufferedReader reader)
570 throws IOException {
571
572 for (line = reader.readLine(); line != null; line = reader.readLine()) {
573 ++lineNumber;
574 for (Section section : sections) {
575 if (section.matchesHeader(line)) {
576 return section;
577 }
578 }
579 }
580
581 // we have reached end of file and not found a matching section header
582 return null;
583
584 }
585
586 /** Read X, Y, UT1-UTC.
587 * @param section section to parse
588 * @param reader reader from where file content is obtained
589 * @param name name of the file (or zip entry)
590 * @exception IOException if data can't be read
591 */
592 private void loadXYDT(final Section section, final BufferedReader reader, final String name)
593 throws IOException {
594
595 boolean inValuesPart = false;
596 for (line = reader.readLine(); line != null; line = reader.readLine()) {
597 lineNumber++;
598 final String[] fields = section.getFields(line);
599 if (fields != null) {
600
601 // we are within the values part
602 inValuesPart = true;
603
604 // this is a data line, build an entry from the extracted fields
605 final int year = Integer.parseInt(fields[0]);
606 final int month = Integer.parseInt(fields[1]);
607 final int day = Integer.parseInt(fields[2]);
608 final int mjd = Integer.parseInt(fields[3]);
609 final DateComponents dc = new DateComponents(DateComponents.MODIFIED_JULIAN_EPOCH, mjd);
610 if ((dc.getYear() % 100) != (year % 100) ||
611 dc.getMonth() != month ||
612 dc.getDay() != day) {
613 throw new OrekitException(OrekitMessages.INCONSISTENT_DATES_IN_IERS_FILE,
614 name, year, month, day, mjd);
615 }
616 mjdMin = FastMath.min(mjdMin, mjd);
617 mjdMax = FastMath.max(mjdMax, mjd);
618 if (firstMJD < 0) {
619 // store the first mjd parsed
620 firstMJD = mjd;
621 }
622
623 // get the entry at the same date if it was already parsed
624 final double[] eop;
625 if (eopFieldsMap.containsKey(mjd)) {
626 eop = eopFieldsMap.get(mjd);
627 } else {
628 eop = new double[4];
629 eopFieldsMap.put(mjd, eop);
630 }
631
632 if (eop[0] <= firstMJD) {
633 // either it is the first time we parse this date (eop[0] = 0),
634 // or the new parsed data is from a more recent file
635 // in both case, we should update the array
636 eop[0] = firstMJD;
637 eop[1] = Double.parseDouble(fields[4]);
638 eop[2] = Double.parseDouble(fields[5]);
639 eop[3] = Double.parseDouble(fields[6]);
640 }
641
642 } else if (inValuesPart) {
643 // we leave values part
644 return;
645 }
646 }
647
648 throw new OrekitException(OrekitMessages.UNEXPECTED_END_OF_FILE_AFTER_LINE,
649 name, lineNumber);
650
651 }
652
653 /** Read EOP data.
654 * @param section section to parse
655 * @param isNonRotatingOrigin if true, the file contain Non-Rotating Origin nutation corrections
656 * @param reader reader from where file content is obtained
657 * @param name name of the file (or zip entry)
658 * @exception IOException if data can't be read
659 */
660 private void loadPoleOffsets(final Section section, final boolean isNonRotatingOrigin,
661 final BufferedReader reader, final String name)
662 throws IOException {
663
664 boolean inValuesPart = false;
665 for (line = reader.readLine(); line != null; line = reader.readLine()) {
666 lineNumber++;
667 final String[] fields = section.getFields(line);
668 if (fields != null) {
669
670 // we are within the values part
671 inValuesPart = true;
672
673 // this is a data line, build an entry from the extracted fields
674 final int mjd = Integer.parseInt(fields[0]);
675 mjdMin = FastMath.min(mjdMin, mjd);
676 mjdMax = FastMath.max(mjdMax, mjd);
677
678 // get the entry at the same date if it was already parsed
679 final double[] pole;
680 if (poleOffsetsFieldsMap.containsKey(mjd)) {
681 pole = poleOffsetsFieldsMap.get(mjd);
682 } else {
683 pole = new double[5];
684 poleOffsetsFieldsMap.put(mjd, pole);
685 }
686
687 if (pole[0] <= firstMJD) {
688 // either it is the first time we parse this date (pole[0] = 0),
689 // or the new parsed data is from a more recent file
690 // in both case, we should update the array
691 pole[0] = firstMJD;
692 if (isNonRotatingOrigin) {
693 pole[1] = Double.parseDouble(fields[1]);
694 pole[2] = Double.parseDouble(fields[2]);
695 } else {
696 pole[3] = Double.parseDouble(fields[1]);
697 pole[4] = Double.parseDouble(fields[2]);
698 }
699 }
700
701 } else if (inValuesPart) {
702 // we leave values part
703 return;
704 }
705 }
706
707 throw new OrekitException(OrekitMessages.UNEXPECTED_END_OF_FILE_AFTER_LINE,
708 name, lineNumber);
709
710 }
711
712 }
713
714 }