ucar.unidata.geoloc.projection.sat

Class GEOSTransform

java.lang.Object

ucar.unidata.geoloc.projection.sat.GEOSTransform

public class GEOSTransform
extends Object

Geostationary Transform

Since:

08/28/2014

Author:

Tom Rink

Field Summary

Fields

Modifier and Type	Field and Description
static String	GEOS
static String	GOES
ucar.unidata.geoloc.projection.sat.GEOSTransform.Geoid	grs80
static String	GRS80
String	scan_geom
ucar.unidata.geoloc.projection.sat.GEOSTransform.Geoid	wgs84
static String	WGS84

Constructor Summary

Constructors

Constructor and Description
GEOSTransform()
GEOSTransform(double subLonDegrees)
GEOSTransform(double subLonDegrees, double perspective_point_height, double semi_minor_axis, double semi_major_axis, double inverse_flattening, String sweep_angle_axis)
GEOSTransform(double subLonDegrees, double perspective_point_height, double semi_minor_axis, double semi_major_axis, String sweep_angle_axis)
GEOSTransform(double subLonDegrees, String scan_geom)
GEOSTransform(double subLonDegrees, String scan_geom, String geoidID)

Method Summary

Methods

Modifier and Type	Method and Description
int[]	earthToElemLine(double geographic_lon, double geographic_lat, double scale_x, double offset_x, double scale_y, double offset_y) Transform pixel center Earth coordinates (lon,lat) to integer FGF coordinates.
double[]	earthToFGF(double geographic_lon, double geographic_lat, double scale_x, double offset_x, double scale_y, double offset_y) Transform Earth coordinates (lon,lat) to fractional FGF coordinates.
double[]	earthToSat(double geographic_lon, double geographic_lat) Transform geographic Earth coordinates to satellite view angle coordinate system also known as the "intermediate" coordinate system in CGMS Normalized Geostationary Projection.
double[]	elemLineToEarth(int elem, int line, double scale_x, double offset_x, double scale_y, double offset_y) Transform integer FGF coordinates to (longitude, latitude) of pixel center The (i,j) pixel, zero-based, refers to the pixel center.
boolean	equals(Object obj)
double[]	FGFtoEarth(double fgf_x, double fgf_y, double scale_x, double offset_x, double scale_y, double offset_y) Transform fractional FGF coordinates to (longitude, latitude).
double[]	FGFtoSat(double fgf_x, double fgf_y, double scale_x, double offset_x, double scale_y, double offset_y) Transform fractional FGF coordinates to (lamda, theta) radians.
double[]	GOES_to_GEOS(double lamda_goes, double theta_goes) Transform view angle coordinates in the GOES scan geometry frame to view angle coordinates in the GEOS scan geometry frame.
double[]	satToEarth(double x, double y) Transform satellite view angle coordinates, known as the "intermeidate" coordinates in the CGMS Normalized Geostationary Projection, to geographic Earth coordinates.
double[]	SatToFGF(double lamda, double theta, double scale_x, double offset_x, double scale_y, double offset_y) Transform (lamda, theta) in radians to fractional FGF coordinates.

Methods inherited from class java.lang.Object

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

Field Detail

GOES

public static final String GOES

See Also:

Constant Field Values

GEOS

public static final String GEOS

See Also:

Constant Field Values

WGS84

public static final String WGS84

See Also:

Constant Field Values

GRS80

public static final String GRS80

See Also:

Constant Field Values

wgs84

public final ucar.unidata.geoloc.projection.sat.GEOSTransform.Geoid wgs84

grs80

public final ucar.unidata.geoloc.projection.sat.GEOSTransform.Geoid grs80

scan_geom

public String scan_geom

Constructor Detail

GEOSTransform

public GEOSTransform()

GEOSTransform

public GEOSTransform(double subLonDegrees)

GEOSTransform

public GEOSTransform(double subLonDegrees,
             String scan_geom)

GEOSTransform

public GEOSTransform(double subLonDegrees,
             String scan_geom,
             String geoidID)

GEOSTransform

public GEOSTransform(double subLonDegrees,
             double perspective_point_height,
             double semi_minor_axis,
             double semi_major_axis,
             double inverse_flattening,
             String sweep_angle_axis)

GEOSTransform

public GEOSTransform(double subLonDegrees,
             double perspective_point_height,
             double semi_minor_axis,
             double semi_major_axis,
             String sweep_angle_axis)

Method Detail

earthToSat

public double[] earthToSat(double geographic_lon,
                  double geographic_lat)

Transform geographic Earth coordinates to satellite view angle coordinate system also known as the "intermediate" coordinate system in CGMS Normalized Geostationary Projection.

Parameters:

geographic_lon - longitude, units: degrees

geographic_lat - latitude, units: degrees

Returns:

(lamda, theta) units: radian. This is the (x,y) or (East-West, North_South) view angle.

satToEarth

public double[] satToEarth(double x,
                  double y)

Transform satellite view angle coordinates, known as the "intermeidate" coordinates in the CGMS Normalized Geostationary Projection, to geographic Earth coordinates.

Parameters:

x - is lamda (East-West) angle, units: radians

y - is theta (Norht-South) angle, units: radians

Returns:

(Longitude, Latitude), units degrees

GOES_to_GEOS

public double[] GOES_to_GEOS(double lamda_goes,
                    double theta_goes)

Transform view angle coordinates in the GOES scan geometry frame to view angle coordinates in the GEOS scan geometry frame.

FGFtoEarth

public double[] FGFtoEarth(double fgf_x,
                  double fgf_y,
                  double scale_x,
                  double offset_x,
                  double scale_y,
                  double offset_y)

Transform fractional FGF coordinates to (longitude, latitude).

Parameters:

fgf_x - fractional FGF coordinate, zero-based

fgf_y - fractional FGF coordinate, zero-based

scale_x - scaleFactor from the x coordinate variable

offset_x - addOffset from the x coordinate variable

scale_y - scaleFactor from the y coordinate variable

offset_y - addOffset from the y coordinate variable

Returns:

(Longitude, Latitude), units: degrees

FGFtoSat

public double[] FGFtoSat(double fgf_x,
                double fgf_y,
                double scale_x,
                double offset_x,
                double scale_y,
                double offset_y)

Transform fractional FGF coordinates to (lamda, theta) radians.

Parameters:

fgf_x - fractional FGF coordinate, zero-based

fgf_y - fractional FGF coordinate, zero-based

scale_x - scaleFactor from the x coordinate variable

offset_x - addOffset from the x coordinate variable

scale_y - scaleFactor from the y coordinate variable

offset_y - addOffset from the y coordinate variable

Returns:

(lamda, theta), units: radians

elemLineToEarth

public double[] elemLineToEarth(int elem,
                       int line,
                       double scale_x,
                       double offset_x,
                       double scale_y,
                       double offset_y)

Transform integer FGF coordinates to (longitude, latitude) of pixel center The (i,j) pixel, zero-based, refers to the pixel center.

Parameters:

scale_x - scaleFactor from the x coordinate variable

offset_x - addOffset from the x coordinate variable

scale_y - scaleFactor from the y coordinate variable

offset_y - addOffset from the y coordinate variable

Returns:

(Longitude, Latitude), units: degrees, of FGF (i,j) pixel center

earthToFGF

public double[] earthToFGF(double geographic_lon,
                  double geographic_lat,
                  double scale_x,
                  double offset_x,
                  double scale_y,
                  double offset_y)

Transform Earth coordinates (lon,lat) to fractional FGF coordinates.

Parameters:

geographic_lon - Longitude, units: degrees

geographic_lat - Latitude, units: degrees

scale_x - scaleFactor from the x coordinate variable

offset_x - addOffset from the x coordinate variable

scale_y - scaleFactor from the y coordinate variable

offset_y - addOffset from the y coordinate variable

Returns:

fractional fgf coordinates

earthToElemLine

public int[] earthToElemLine(double geographic_lon,
                    double geographic_lat,
                    double scale_x,
                    double offset_x,
                    double scale_y,
                    double offset_y)

Transform pixel center Earth coordinates (lon,lat) to integer FGF coordinates.

Parameters:

scale_x - scaleFactor from the x coordinate variable

offset_x - addOffset from the x coordinate variable

scale_y - scaleFactor from the y coordinate variable

offset_y - addOffset from the y coordinate variable

SatToFGF

public double[] SatToFGF(double lamda,
                double theta,
                double scale_x,
                double offset_x,
                double scale_y,
                double offset_y)

Transform (lamda, theta) in radians to fractional FGF coordinates.

Parameters:

scale_x - scaleFactor from the x coordinate variable

offset_x - addOffset from the x coordinate variable

scale_y - scaleFactor from the y coordinate variable

offset_y - addOffset from the y coordinate variable

equals

public boolean equals(Object obj)

Overrides:

equals in class Object