org.ka2ddo.yaac.weather

Class MADISWeatherChecker

java.lang.Object

org.ka2ddo.yaac.weather.MADISWeatherChecker

All Implemented Interfaces:

java.io.Serializable

public class MADISWeatherChecker
extends java.lang.Object
implements java.io.Serializable

This class implements part of the US National Weather Service's MADIS quality checks on weather data. For what weather parameters are available in APRS, it implements the Level 1 (static range) checks, and some of the Level 1 (temporal consistency) checks, as defined at the MADIS quality control website. Note that it uses the SRTM elevation data to qualify some of its checks for weather stations that do not report their elevation, so the Level 1 static barometric pressure check may be disabled or loosened for stations in areas without downloaded SRTM data.

Note that this class is not thread-safe, so a unique instance should be created for each thread using it. Also, all the responses for a given field should be obtained before running another check on a different field or station.

If the level 3 spatial consistency checks are to be performed, this uses the modified Shepard's method for doing the weighted checks, but still splits into 8 octants around the checked station.

Author:

Andrew Pavlin, KA2DDO

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
MADISWeatherChecker() Create an instance of a MADISWeatherChecker.

Method Summary

Modifier and Type	Method and Description
boolean	check(WeatherEnum en, java.util.Map<java.lang.Enum,java.lang.Object> weatherMap, java.util.Map<java.lang.Enum,java.lang.Object> prevWeatherMap, StationState ss) Perform the MADIS checks on the specified weather parameter from an APRS packet with weather data in it.
boolean	check(WeatherEnum en, OpenTracMessage otm, OpenTracMessage prevOTM, StationState ss) Perform the MADIS checks on the specified weather parameter from an OpenTRAC packet with weather data in it.
static float	getMinimumPressureForThisLocation(float altitudeM, double latitude, double longitude) Compute the Level 1 static minimum barometric pressure for a given station location, based on the station's reported altitude if provided, else on the ground elevation at the station's reported latitude/longitude.
static float	getMinimumPressureForThisLocation(StationState ss) Compute the Level 1 static minimum barometric pressure for a given station location, based on the station's reported altitude if provided, else on the ground elevation at the station's reported latitude/longitude.
void	initializeSpatialCheckEnvironment(float maxRngLvl3SpatialKm) Specify that the current known set of weather stations should be used for performing level 3 spatial consistency checks.
boolean	isNotTooOld() Report if the last data record was not out-of-date.
boolean	level1check(WeatherEnum en, java.util.Map<java.lang.Enum,java.lang.Object> weatherMap, StationState ss) Perform only the MADIS Level 1 validity checks on the specified weather parameter from an APRS packet with weather data in it.

Methods inherited from class java.lang.Object

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

Constructor Detail

MADISWeatherChecker

public MADISWeatherChecker()

Create an instance of a MADISWeatherChecker.

Method Detail

getMinimumPressureForThisLocation

public static float getMinimumPressureForThisLocation(StationState ss)

Compute the Level 1 static minimum barometric pressure for a given station location, based on the station's reported altitude if provided, else on the ground elevation at the station's reported latitude/longitude.

Parameters:

ss - StationState to obtain station location from

Returns:

minimum sane barometric pressure for this location's elevation in tenths of millibars

getMinimumPressureForThisLocation

public static float getMinimumPressureForThisLocation(float altitudeM,
                                                      double latitude,
                                                      double longitude)

Compute the Level 1 static minimum barometric pressure for a given station location, based on the station's reported altitude if provided, else on the ground elevation at the station's reported latitude/longitude.

Parameters:

altitudeM - reported altitude in meters, or Float.NaN if not known

latitude - reported latitude in fractional degrees North

longitude - reported longitude in fractional degrees East

Returns:

minimum sane barometric pressure for this location's elevation in tenths of millibars

isNotTooOld

public boolean isNotTooOld()

Report if the last data record was not out-of-date.

Returns:

boolean true if data is recent enough to be considered valid

initializeSpatialCheckEnvironment

public void initializeSpatialCheckEnvironment(float maxRngLvl3SpatialKm)

Specify that the current known set of weather stations should be used for performing level 3 spatial consistency checks. Note that this should be called immediately before a chronologically "tight" set of tests so that the weather station data used for the tests is reasonably current and accurate.

Parameters:

maxRngLvl3SpatialKm - the maximum range (in kilometers) from the station under test to another station for that other station to be considered as a test reference

check

public boolean check(WeatherEnum en,
                     java.util.Map<java.lang.Enum,java.lang.Object> weatherMap,
                     java.util.Map<java.lang.Enum,java.lang.Object> prevWeatherMap,
                     StationState ss)

Perform the MADIS checks on the specified weather parameter from an APRS packet with weather data in it. Once check() returns with the validity response, call isNotTooOld() to get the age results.

Parameters:

en - WeatherEnum to identify the weather parameter to check

weatherMap - Map of current weather data from APRS packet

prevWeatherMap - earlier APRS packet's weather data Map from same station to use for time variation checks

ss - StationState of station being checked

Returns:

boolean true if weather parameter is invalid for some reason

level1check

public boolean level1check(WeatherEnum en,
                           java.util.Map<java.lang.Enum,java.lang.Object> weatherMap,
                           StationState ss)

Perform only the MADIS Level 1 validity checks on the specified weather parameter from an APRS packet with weather data in it.

Parameters:

en - WeatherEnum to identify the weather parameter to check

weatherMap - Map of current weather data from APRS packet

ss - StationState of station being checked

Returns:

boolean true if weather parameter is invalid for some reason

check

public boolean check(WeatherEnum en,
                     OpenTracMessage otm,
                     OpenTracMessage prevOTM,
                     StationState ss)

Perform the MADIS checks on the specified weather parameter from an OpenTRAC packet with weather data in it. Once check() returns with the validity response, call isNotTooOld() to get the age results.

Parameters:

en - WeatherEnum to identify the weather parameter to check

otm - OpenTracMessage packet to analyze

prevOTM - earlier OpenTracMessage packet from same station to use for time variation checks

ss - StationState of station being checked

Returns:

boolean true if weather parameter is invalid for some reason