Package org.apache.sis.measure

## Class Longitude

- Object
- - Angle
  - - Longitude

- All Implemented Interfaces:
    `Serializable`, `Comparable<Angle>`, `Formattable`

      public final class Longitude
      extends Angle

  A longitude angle in decimal degrees. Positive longitudes are East, while negative longitudes are West. The longitude symbol is the Greek lower-case letter lambda (λ).

  Longitudes are not necessarily relative to the Greenwich meridian. The prime meridian depends on the context, typically specified through the geodetic datum of a geographic CRS.

  Immutability and thread safety
  This final class is immutable and thus inherently thread-safe.
  Since:
    0.3
  See Also:
    `Latitude`, `AngleFormat`, `CoordinateFormat`, Serialized Form

  Defined in the `sis-utility` module

- - ### Field Summary

    Fields
    Modifier and Type | Field | Description
    --- | --- | ---
    `static double` | `MAX_VALUE` | Maximum usual value for longitude (+180.0°).
    `static double` | `MIN_VALUE` | Minimum usual value for longitude (-180.0°).

  - ### Constructor Summary

    Constructors
    Constructor | Description
    --- | ---
    `Longitude​(double λ)` | Construct a new longitude with the specified angular value.
    `Longitude​(String string)` | Constructs a newly allocated `Longitude` object that contain the angular value represented by the string.
    `Longitude​(DirectPosition position)` | Constructs a newly allocated object containing the longitude value of the given position.

  - ### Method Summary

    All Methods Static Methods Concrete Methods
    Modifier and Type | Method | Description
    --- | --- | ---
    `static double` | `normalize​(double λ)` | Returns the given longitude value normalized to the [-180 … 180)° range (upper value is exclusive).

    - ### Methods inherited from class Angle

      `compareTo, degrees, equals, formatTo, hashCode, radians, toString`

    - ### Methods inherited from class Object

      `clone, finalize, getClass, notify, notifyAll, wait, wait, wait`

- - ### Field Detail

    - #### MIN_VALUE

          public static final double MIN_VALUE

      Minimum usual value for longitude (-180.0°).
      See Also:
        `DefaultCoordinateSystemAxis​.getMinimumValue()`, Constant Field Values

    - #### MAX_VALUE

          public static final double MAX_VALUE

      Maximum usual value for longitude (+180.0°).
      See Also:
        `DefaultCoordinateSystemAxis​.getMaximumValue()`, Constant Field Values

  - ### Constructor Detail

    - #### Longitude

          public Longitude​(double λ)

      Construct a new longitude with the specified angular value. This constructor does not normalize the given value.
      Parameters:
        `\u03bb` - longitude value in decimal degrees.

    - #### Longitude

          public Longitude​(String string)
                    throws NumberFormatException

      Constructs a newly allocated `Longitude` object that contain the angular value represented by the string. The string should represent an angle in either fractional degrees (e.g. 45.5°) or degrees with minutes and seconds (e.g. 45°30'). The hemisphere (E or W) is optional (default to East).

      This is a convenience constructor mostly for testing purpose, since it uses a fixed locale. Developers should consider using `AngleFormat` for end-user applications instead than this constructor.

      Parameters:
        `string` - a string to be converted to a `Longitude`.
      Throws:
        `NumberFormatException` - if the string does not contain a parsable angle, or represents a longitude angle.
      See Also:
        `AngleFormat​.parse(String)`

    - #### Longitude

          public Longitude​(DirectPosition position)
                    throws IllegalArgumentException

      Constructs a newly allocated object containing the longitude value of the given position. For this method, the longitude value is defined as the angular value associated to the first axis oriented toward East or West. Note that this is not necessarily the geodetic longitudes used in geographic CRS; it may also be geocentric longitudes.

      If the axis direction is West, then the sign of the coordinate value is inverted. If the coordinate value uses another angular units than degrees, then a unit conversion is applied.

      Parameters:
        `position` - the coordinate from which to extract the longitude value in degrees.
      Throws:
        `IllegalArgumentException` - if the given coordinate it not associated to a CRS, or if no axis oriented toward East or West is found, or if that axis does not use angular units.
      Since:
        0.8

  - ### Method Detail

    - #### normalize

          public static double normalize​(double λ)

      Returns the given longitude value normalized to the [-180 … 180)° range (upper value is exclusive). If the given value is outside the longitude range, then this method adds or subtracts a multiple of 360° in order to bring back the value to that range.

      Special cases:

      - NaN values are returned unchanged
      - ±∞ are mapped to NaN
      - ±180° are both mapped to -180° (i.e. the range is from -180° inclusive to +180° exclusive)
      - ±0 are returned unchanged (i.e. the sign of negative and positive zero is preserved)
      Note that the given value should not be greater than 4×10⁸ degrees if a centimetric precision is desired.
      Parameters:
        `\u03bb` - the longitude value in decimal degrees.
      Returns:
        the given value normalized to the [-180 … 180)° range, or NaN if the given value was NaN of infinite.
      Since:
        0.4
      See Also:
        `Latitude​.clamp(double)`