FESCHatEpsilonReader.java
- /* Copyright 2002-2020 CS GROUP
- * Licensed to CS GROUP (CS) under one or more
- * contributor license agreements. See the NOTICE file distributed with
- * this work for additional information regarding copyright ownership.
- * CS licenses this file to You under the Apache License, Version 2.0
- * (the "License"); you may not use this file except in compliance with
- * the License. You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- package org.orekit.forces.gravity.potential;
- import java.io.BufferedReader;
- import java.io.IOException;
- import java.io.InputStream;
- import java.io.InputStreamReader;
- import java.nio.charset.StandardCharsets;
- import java.util.Map;
- import java.util.regex.Matcher;
- import java.util.regex.Pattern;
- import org.hipparchus.util.FastMath;
- import org.hipparchus.util.SinCos;
- import org.orekit.errors.OrekitException;
- import org.orekit.errors.OrekitMessages;
- /** Reader for ocean tides files following the fes2004.dat format.
- * @since 6.1
- * @author Luc Maisonobe
- */
- public class FESCHatEpsilonReader extends OceanTidesReader {
- /** Default pattern for fields with unknown type (non-space characters). */
- private static final String UNKNOWN_TYPE_PATTERN = "\\S+";
- /** Pattern for fields with integer type. */
- private static final String INTEGER_TYPE_PATTERN = "[-+]?\\p{Digit}+";
- /** Pattern for fields with real type. */
- private static final String REAL_TYPE_PATTERN = "[-+]?(?:(?:\\p{Digit}+(?:\\.\\p{Digit}*)?)|(?:\\.\\p{Digit}+))(?:[eE][-+]?\\p{Digit}+)?";
- /** Pattern for fields with Doodson number. */
- private static final String DOODSON_TYPE_PATTERN = "\\p{Digit}{2,3}[.,]\\p{Digit}{3}";
- /** Pattern for regular data. */
- private static final Pattern PATTERN = Pattern.compile("[.,]");
- /** Sea water fensity. */
- private static final double RHO = 1025;
- /** Gravitational constant (from IERS 2010, chapter 1). */
- private static final double BIG_G = 6.67428e-11;
- /** Earth mean gravity AT EQUATOR (from IERS 2010, chapter 1). */
- private static final double GE = 9.7803278;
- /** Scale of the CHat parameters. */
- private final double scaleCHat;
- /** Scale of the epsilon parameters. */
- private final double scaleEpsilon;
- /** Load deformation coefficients for ocean tides. */
- private final OceanLoadDeformationCoefficients oldc;
- /** Map for astronomical amplitudes. */
- private final Map<Integer, Double> astronomicalAmplitudes;
- /** Simple constructor.
- * @param supportedNames regular expression for supported files names
- * @param scaleCHat scale of the CHat parameters
- * @param scaleEpsilon scale of the epsilon parameters
- * @param oldc load deformation coefficients for ocean tides
- * @param astronomicalAmplitudes map for astronomical amplitudes
- * @see AstronomicalAmplitudeReader#getAstronomicalAmplitudesMap()
- */
- public FESCHatEpsilonReader(final String supportedNames,
- final double scaleCHat, final double scaleEpsilon,
- final OceanLoadDeformationCoefficients oldc,
- final Map<Integer, Double> astronomicalAmplitudes) {
- super(supportedNames);
- this.scaleCHat = scaleCHat;
- this.scaleEpsilon = scaleEpsilon;
- this.oldc = oldc;
- this.astronomicalAmplitudes = astronomicalAmplitudes;
- }
- /** {@inheritDoc} */
- @Override
- public void loadData(final InputStream input, final String name)
- throws IOException {
- // FES ocean tides models have the following form:
- // Ocean tide model: FES2004 normalized model (fev. 2004) up to (100,100) in cm
- // (long period from FES2002 up to (50,50) + equilibrium Om1/Om2, atmospheric tide NOT included)
- // Doodson Darw n m Csin+ Ccos+ Csin- Ccos- C+ eps+ C- eps-
- // 55.565 Om1 2 0 -0.540594 0.000000 0.000000 0.000000 0.5406 270.000 0.0000 0.000
- // 55.575 Om2 2 0 -0.005218 0.000000 0.000000 0.000000 0.0052 270.000 0.0000 0.000
- // 56.554 Sa 1 0 0.017233 0.000013 0.000000 0.000000 0.0172 89.957 0.0000 0.000
- // 56.554 Sa 2 0 -0.046604 -0.000903 0.000000 0.000000 0.0466 268.890 0.0000 0.000
- // 56.554 Sa 3 0 -0.000889 0.000049 0.000000 0.000000 0.0009 273.155 0.0000 0.000
- final String[] fieldsPatterns = new String[] {
- DOODSON_TYPE_PATTERN,
- UNKNOWN_TYPE_PATTERN,
- INTEGER_TYPE_PATTERN,
- INTEGER_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN,
- REAL_TYPE_PATTERN
- };
- final StringBuilder builder = new StringBuilder("^\\p{Space}*");
- for (int i = 0; i < fieldsPatterns.length; ++i) {
- builder.append("(");
- builder.append(fieldsPatterns[i]);
- builder.append(")");
- builder.append((i < fieldsPatterns.length - 1) ? "\\p{Space}+" : "\\p{Space}*$");
- }
- final Pattern regularLinePattern = Pattern.compile(builder.toString());
- final double commonFactor = 4 * FastMath.PI * BIG_G * RHO / GE;
- final double[] kPrime = oldc.getCoefficients();
- // parse the file
- startParse(name);
- try (BufferedReader r = new BufferedReader(new InputStreamReader(input, StandardCharsets.UTF_8))) {
- int lineNumber = 0;
- for (String line = r.readLine(); line != null; line = r.readLine()) {
- ++lineNumber;
- final Matcher regularMatcher = regularLinePattern.matcher(line);
- if (regularMatcher.matches()) {
- // we have found a regular data line
- // parse fields
- final int doodson = Integer.parseInt(PATTERN.matcher(regularMatcher.group(1)).replaceAll(""));
- final int n = Integer.parseInt(regularMatcher.group(3));
- final int m = Integer.parseInt(regularMatcher.group(4));
- if (canAdd(n, m)) {
- final double cHatPlus = scaleCHat * Double.parseDouble(regularMatcher.group(9));
- final double ePlus = scaleEpsilon * Double.parseDouble(regularMatcher.group(10));
- final double cHatMinus = scaleCHat * Double.parseDouble(regularMatcher.group(11));
- final double eMinus = scaleEpsilon * Double.parseDouble(regularMatcher.group(12));
- // compute bias from table 6.6
- final double hf = astronomicalAmplitudes.getOrDefault(doodson, 0.0);
- final int cGamma = doodson / 100000;
- final double chiF;
- if (cGamma == 0) {
- chiF = hf > 0 ? FastMath.PI : 0.0;
- } else if (cGamma == 1) {
- chiF = hf > 0 ? 0.5 * FastMath.PI : -0.5 * FastMath.PI;
- } else if (cGamma == 2) {
- chiF = hf > 0 ? 0.0 : FastMath.PI;
- } else {
- chiF = 0;
- }
- // compute reference gravity coefficients by converting height coefficients
- // IERS conventions 2010, equation 6.21
- if (n >= kPrime.length) {
- throw new OrekitException(OrekitMessages.OCEAN_TIDE_LOAD_DEFORMATION_LIMITS,
- kPrime.length - 1, n, name);
- }
- final double termFactor = (1 + kPrime[n]) / (2 * n + 1);
- // an update on IERS conventions from 2012-08-10 states that for FES model:
- // Note that, for zonal terms, FES2004 takes the approach to set
- // the retrograde coefficients C-f,nO and S-f,n0 to zero and to double
- // the prograde coefficients C+f,nO and S+f,n0. Therefore, after
- // applying Equation (6.15), the ΔCn0 have the expected value but the
- // ΔSn0 must be set to zero.
- // (see ftp://tai.bipm.org/iers/convupdt/chapter6/icc6.pdf)
- final SinCos scP = FastMath.sinCos(ePlus + chiF);
- final SinCos scM = FastMath.sinCos(eMinus + chiF);
- final double cPlus = commonFactor * termFactor * cHatPlus * scP.sin();
- final double sPlus = commonFactor * termFactor * cHatPlus * scP.cos();
- final double cMinus = (m == 0) ? 0.0 : commonFactor * termFactor * cHatMinus * scM.sin();
- final double sMinus = (m == 0) ? 0.0 : commonFactor * termFactor * cHatMinus * scM.cos();
- // store parsed fields
- addWaveCoefficients(doodson, n, m, cPlus, sPlus, cMinus, sMinus, lineNumber, line);
- }
- }
- }
- }
- endParse();
- }
- }