ucar.nc2.iosp.nexrad2
Class Level2Record

java.lang.Object
  ucar.nc2.iosp.nexrad2.Level2Record

public class Level2Record
extends java.lang.Object

This class reads one record (radial) in an NEXRAD level II file. File must be uncompressed. Not handling messages yet, only data.

10/16/05: Now returns data as a byte, so use scale and offset. Adapted with permission from the Java Iras software developed by David Priegnitz at NSSL.

Author:

caron, David Priegnitz

Field Summary

static byte	BELOW_THRESHOLD
static int	CORRELATION_COEFFICIENT High Resolution Sprectrum Width moment identifier
static int	DIFF_PHASE High Resolution Radial Velocity moment identifier
static int	DIFF_REFLECTIVITY_HIGH High Resolution Radial Velocity moment identifier
static int	DOPPLER_RESOLUTION_HIGH_CODE High doppler resolution code
static int	DOPPLER_RESOLUTION_LOW_CODE Low doppler resolution code
static float	HORIZONTAL_BEAM_WIDTH Horizontal beam width
byte	message_type
static byte	MISSING_DATA Initialization flag for lookup tables public static int data_lut_init_flag = 0; /** Reflectivity look up table public static float[] Reflectivity_LUT = new float[256]; /** 1 km Velocity look up table public static float[] Velocity_1km_LUT = new float[256]; /** 1/2 km Velocity look up table public static float[] Velocity_hkm_LUT = new float[256]; static { Reflectivity_LUT[0] = 0.0f; // Float.NaN; //(float) SIGNAL_BELOW_THRESHOLD; Reflectivity_LUT[1] = Float.NaN; //(float) SIGNAL_OVERLAID; Velocity_1km_LUT[0] = 0.0f; // Float.NaN; //(float) SIGNAL_BELOW_THRESHOLD; Velocity_1km_LUT[1] = Float.NaN; //(float) SIGNAL_OVERLAID; Velocity_hkm_LUT[0] = 0.0f; // Float.NaN; //(float) SIGNAL_BELOW_THRESHOLD; Velocity_hkm_LUT[1] = Float.NaN; //(float) SIGNAL_OVERLAID; for (int i = 2; i < 256; i++) { Reflectivity_LUT[i] = (float) (i / 2.0 - 33.0); Velocity_1km_LUT[i] = (float) (i - 129.0); Velocity_hkm_LUT[i] = (float) (i / 2.0 - 64.5); // also spectrum width } }
static int	REFLECTIVITY Reflectivity moment identifier
static int	REFLECTIVITY_HIGH
static int	SPECTRUM_WIDTH Sprectrum Width moment identifier
static int	SPECTRUM_WIDTH_HIGH High Resolution Sprectrum Width moment identifier
static int	VELOCITY_HI Radial Velocity moment identifier
static int	VELOCITY_HIGH High Resolution Radial Velocity moment identifier
static int	VELOCITY_LOW Radial Velocity moment identifier

Constructor Summary

Level2Record(RandomAccessFile din, int record, long message_offset31)

Method Summary

boolean	checkOk()
void	dump(java.io.PrintStream out)
void	dump2(java.io.PrintStream out)
void	dumpMessage(java.io.PrintStream out)
static Level2Record	factory(RandomAccessFile din, int record, long message_offset31)
float	getAzimuth() Get the azimuth in degrees
float	getDatatypeAddOffset(int datatype)
static java.lang.String	getDatatypeName(int datatype)
short	getDatatypeRangeFoldingThreshhold(int datatype)
float	getDatatypeScaleFactor(int datatype)
short	getDatatypeSNRThreshhold(int datatype)
static java.lang.String	getDatatypeUnits(int datatype)
java.util.Date	getDate()
static java.util.Date	getDate(int julianDays, int msecs)
float	getElevation() Get the elevation angle in degrees
int	getGateCount(int datatype) This method returns the number of gates
int	getGateSize(int datatype) This method returns the gate size in meters
int	getGateStart(int datatype) This method returns the starting gate in meters
static java.lang.String	getMessageTypeName(int code)
static java.lang.String	getRadialStatusName(int code)
static java.lang.String	getVolumeCoveragePatternName(int code)
void	readData(RandomAccessFile raf, int datatype, Range gateRange, IndexIterator ii) Read data from this record.
java.lang.String	toString() Instances which have same content are equal.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

REFLECTIVITY

public static final int REFLECTIVITY

Reflectivity moment identifier

See Also:

Constant Field Values

VELOCITY_HI

public static final int VELOCITY_HI

Radial Velocity moment identifier

See Also:

Constant Field Values

VELOCITY_LOW

public static final int VELOCITY_LOW

Radial Velocity moment identifier

See Also:

Constant Field Values

SPECTRUM_WIDTH

public static final int SPECTRUM_WIDTH

Sprectrum Width moment identifier

See Also:

Constant Field Values

DOPPLER_RESOLUTION_LOW_CODE

public static final int DOPPLER_RESOLUTION_LOW_CODE

Low doppler resolution code

See Also:

Constant Field Values

DOPPLER_RESOLUTION_HIGH_CODE

public static final int DOPPLER_RESOLUTION_HIGH_CODE

High doppler resolution code

See Also:

Constant Field Values

HORIZONTAL_BEAM_WIDTH

public static final float HORIZONTAL_BEAM_WIDTH

Horizontal beam width

See Also:

Constant Field Values

REFLECTIVITY_HIGH

public static final int REFLECTIVITY_HIGH

See Also:

Constant Field Values

VELOCITY_HIGH

public static final int VELOCITY_HIGH

High Resolution Radial Velocity moment identifier

See Also:

Constant Field Values

SPECTRUM_WIDTH_HIGH

public static final int SPECTRUM_WIDTH_HIGH

High Resolution Sprectrum Width moment identifier

See Also:

Constant Field Values

DIFF_REFLECTIVITY_HIGH

public static final int DIFF_REFLECTIVITY_HIGH

High Resolution Radial Velocity moment identifier

See Also:

Constant Field Values

DIFF_PHASE

public static final int DIFF_PHASE

High Resolution Radial Velocity moment identifier

See Also:

Constant Field Values

CORRELATION_COEFFICIENT

public static final int CORRELATION_COEFFICIENT

High Resolution Sprectrum Width moment identifier

See Also:

Constant Field Values

MISSING_DATA

public static final byte MISSING_DATA

Initialization flag for lookup tables public static int data_lut_init_flag = 0; /** Reflectivity look up table public static float[] Reflectivity_LUT = new float[256]; /** 1 km Velocity look up table public static float[] Velocity_1km_LUT = new float[256]; /** 1/2 km Velocity look up table public static float[] Velocity_hkm_LUT = new float[256]; static { Reflectivity_LUT[0] = 0.0f; // Float.NaN; //(float) SIGNAL_BELOW_THRESHOLD; Reflectivity_LUT[1] = Float.NaN; //(float) SIGNAL_OVERLAID; Velocity_1km_LUT[0] = 0.0f; // Float.NaN; //(float) SIGNAL_BELOW_THRESHOLD; Velocity_1km_LUT[1] = Float.NaN; //(float) SIGNAL_OVERLAID; Velocity_hkm_LUT[0] = 0.0f; // Float.NaN; //(float) SIGNAL_BELOW_THRESHOLD; Velocity_hkm_LUT[1] = Float.NaN; //(float) SIGNAL_OVERLAID; for (int i = 2; i < 256; i++) { Reflectivity_LUT[i] = (float) (i / 2.0 - 33.0); Velocity_1km_LUT[i] = (float) (i - 129.0); Velocity_hkm_LUT[i] = (float) (i / 2.0 - 64.5); // also spectrum width } }

See Also:

Constant Field Values

BELOW_THRESHOLD

public static final byte BELOW_THRESHOLD

See Also:

Constant Field Values

message_type

public byte message_type

Constructor Detail

Level2Record

public Level2Record(RandomAccessFile din,
                    int record,
                    long message_offset31)
             throws java.io.IOException

Throws:

java.io.IOException

Method Detail

getDatatypeName

public static java.lang.String getDatatypeName(int datatype)

getDatatypeUnits

public static java.lang.String getDatatypeUnits(int datatype)

getDatatypeSNRThreshhold

public short getDatatypeSNRThreshhold(int datatype)

getDatatypeRangeFoldingThreshhold

public short getDatatypeRangeFoldingThreshhold(int datatype)

getDatatypeScaleFactor

public float getDatatypeScaleFactor(int datatype)

getDatatypeAddOffset

public float getDatatypeAddOffset(int datatype)

getMessageTypeName

public static java.lang.String getMessageTypeName(int code)

getRadialStatusName

public static java.lang.String getRadialStatusName(int code)

getVolumeCoveragePatternName

public static java.lang.String getVolumeCoveragePatternName(int code)

getDate

public static java.util.Date getDate(int julianDays,
                                     int msecs)

factory

public static Level2Record factory(RandomAccessFile din,
                                   int record,
                                   long message_offset31)
                            throws java.io.IOException

Throws:

java.io.IOException

dumpMessage

public void dumpMessage(java.io.PrintStream out)

dump

public void dump(java.io.PrintStream out)

dump2

public void dump2(java.io.PrintStream out)

checkOk

public boolean checkOk()

getAzimuth

public float getAzimuth()

Get the azimuth in degrees

Returns:

azimuth angle in degrees 0 = true north, 90 = east

getElevation

public float getElevation()

Get the elevation angle in degrees

Returns:

elevation angle in degrees 0 = parellel to pedestal base, 90 = perpendicular

getGateSize

public int getGateSize(int datatype)

This method returns the gate size in meters

Parameters:

datatype - which type of data : REFLECTIVITY, VELOCITY_HI, VELOCITY_LO, SPECTRUM_WIDTH

Returns:

the gate size in meters

getGateStart

public int getGateStart(int datatype)

This method returns the starting gate in meters

Parameters:

datatype - which type of data : REFLECTIVITY, VELOCITY_HI, VELOCITY_LO, SPECTRUM_WIDTH

Returns:

the starting gate in meters

getGateCount

public int getGateCount(int datatype)

This method returns the number of gates

Parameters:

datatype - which type of data : REFLECTIVITY, VELOCITY_HI, VELOCITY_LO, SPECTRUM_WIDTH

Returns:

the number of gates

getDate

public java.util.Date getDate()

readData

public void readData(RandomAccessFile raf,
                     int datatype,
                     Range gateRange,
                     IndexIterator ii)
              throws java.io.IOException

Read data from this record.

Parameters:

raf - read from this file

datatype - which type of data : REFLECTIVITY, VELOCITY_HI, VELOCITY_LO, SPECTRUM_WIDTH

gateRange - handles the possible subset of data to return

ii - put the data here

Throws:

java.io.IOException - on read error

toString

public java.lang.String toString()

Instances which have same content are equal. public boolean equals(Object oo) { if (this == oo) return true; if ( !(oo instanceof Level2Record)) return false; return hashCode() == oo.hashCode(); } /** Override Object.hashCode() to implement equals. * public int hashCode() { if (hashCode == 0) { int result = 17; result = 37*result + elevation_num; //result = 37*result + cut; //result = 37*result + datatype; hashCode = result; } return hashCode; } private volatile int hashCode = 0;

Overrides:

toString in class java.lang.Object