001 /**
002 *
003 */
004 package org.wdssii.core;
005
006 import java.util.Date;
007
008 /**
009 * @author lakshman
010 *
011 */
012 public class RadialSet extends DataType {
013 private final float elevation;
014
015 protected final Radial[] radials;
016
017 private final CPoint radarLocation;
018
019 private final CVector myUx;
020
021 private final CVector myUy;
022
023 private final CVector myUz;
024
025 private final float rangeToFirstGate;
026
027 /**
028 * {@inheritDoc}
029 * @param master
030 */
031 public RadialSet(RadialSet master){
032 super(master);
033 this.elevation = master.elevation;
034 this.radials = new Radial[ master.radials.length ];
035 for (int i=0; i < radials.length; ++i){
036 radials[i] = new Radial( master.radials[i] );
037 }
038 this.radarLocation = master.radarLocation;
039 this.myUx = master.myUx;
040 this.myUy = master.myUy;
041 this.myUz = master.myUz;
042 this.rangeToFirstGate = master.rangeToFirstGate;
043 }
044
045 public RadialSet(float elevation, Location radarLoc, Date scanTime,
046 float rangeToFirstGate,
047 String typeName, Radial[] radials) {
048 super(radarLoc, scanTime, typeName);
049 this.radials = radials;
050 this.elevation = elevation;
051 this.rangeToFirstGate = rangeToFirstGate;
052 // set up the co-ordinate system
053 radarLocation = originLocation.getCPoint();
054 myUz = radarLocation.minus(new CPoint(0, 0, 0)).unit();
055 myUx = new CVector(0, 0, 1).crossProduct(myUz).unit();
056 myUy = myUz.crossProduct(myUx);
057 }
058
059 public float getElevation() {
060 return elevation;
061 }
062
063 /** meters */
064 public float getRangeToFirstGateKms() {
065 return rangeToFirstGate;
066 }
067
068 /**
069 * beamwidth of first radial, or 1 degree if there is no radial.
070 */
071 public float getBeamWidth() {
072 if (radials.length > 0)
073 return getRadial(0).getBeamWidth();
074 return 1;
075 }
076
077 /**
078 * nyquist of first radial, or 0 if there is no radial.
079 */
080 public float getNyquist() {
081 if (radials.length > 0)
082 return getRadial(0).getNyquist();
083 return 0;
084 }
085
086 /**
087 * mean azimuthal spacing of all radials.
088 */
089 public float getAzimuthalSpacing() {
090 float as = 0;
091 for (Radial r : radials){
092 as += r.getAzimuthalSpacing();
093 }
094 float result = (radials.length <= 1)? as : (as / radials.length);
095 return result;
096 }
097
098 /**
099 * gatewidth of first radial, or 1 km if there is no radial.
100 */
101 public float getGateWidthKms() {
102 if (radials.length > 0)
103 return getRadial(0).getGateWidthKms();
104 return 1.0f;
105 }
106
107 /**
108 * number of gates of first radial, or 0 if there is no radial.
109 */
110 public int getNumGates() {
111 if (radials.length > 0)
112 return getRadial(0).getNumGates();
113 return 0;
114 }
115
116 public int getNumRadials() {
117 return radials.length;
118 }
119
120 public Location getRadarLocation() {
121 return originLocation;
122 }
123
124 public CPoint getRadarCPoint() {
125 return radarLocation;
126 }
127
128 public Radial[] getRadials() {
129 return radials;
130 }
131
132 public Radial getRadial(int index) {
133 return radials[index];
134 }
135
136 /** @return 0 if vcp is unknown. */
137 int getVCP() {
138 try {
139 return Integer.parseInt(getAttribute("vcp").toString());
140 } catch (Exception e) {
141 // number format, null, etc.
142 return 0;
143 }
144 }
145
146 public double getRawValue(float az, float rn) {
147 Radial r = getRadial(az);
148 if (r == null)
149 return MissingData;
150 return r.getRawValue(rn);
151 }
152
153 /**
154 * a very slow implementation
155 *
156 * @see NormalizedRadialSet.
157 */
158 public Radial getRadial(float az) {
159 // move backwards to get more recent radials first
160 for (int i = radials.length - 1; i >= 0; --i) {
161 Radial r = getRadial(i);
162 if (r.contains(az))
163 return r;
164 }
165 return null;
166 }
167
168 public double getRawValue(Location loc) {
169 return getRawValue(loc.getCPoint());
170 }
171
172 public double getRawValue(CPoint pt) {
173 // vector from radar location to point
174 // in earth-based co-ordinate system
175 CVector fromConeApex = pt.minus(radarLocation);
176 return getValueInConicalSpace(fromConeApex);
177 }
178
179 /** returns the location of this point in space. */
180 public CPoint getLocation(int radialno, int gateno) {
181 return getRadial(radialno).getLocation(elevation, gateno,
182 radarLocation, myUx, myUy, myUz);
183 }
184
185 /**
186 * The CVector here should in a co-ordinate system where the radar location
187 * is the origin, and the z-axis is perpendicular to the earth's surface,
188 * and the y-axis is north-ward.
189 */
190 public double getValueInConicalSpace(CVector v) {
191 if (radials.length == 0)
192 return MissingData;
193
194 Radial first = getRadial(0);
195 double norm = v.norm();
196 double gw = first.getGateWidthKms();
197 if (norm < gw)
198 return MissingData; // before first gate ..
199
200 // what is the elevation of this point?
201 double bw = first.getBeamWidth();
202 double elev = Math.asin(v.dotProduct(myUz) / norm) * 180 / Math.PI;
203 double elev_diff = elev - elevation;
204 if (elev_diff > bw)
205 return MissingData;
206
207 // within this elevation ...
208 // find az (range approximately equals the norm)
209 CVector vxy = v.crossProduct(myUz);
210 double dotx = vxy.dotProduct(myUx);
211 double doty = vxy.dotProduct(myUy);
212 double az = 180 + Math.atan2(doty, dotx) * 180 / Math.PI;
213 az = Radial.normalizeAzimuth((float) az);
214 return getRawValue((float) az, (float) norm);
215 }
216
217 /** debugging output */
218 public String toStringDB() {
219 String s = "RadialSet " + getTypeName() + " at " + elevation + " has "
220 + radials.length + " radials." + " the first:\n"
221 + getRadial(0).toStringDB() + super.toStringDB();
222 return s;
223 }
224
225 }