## org.opengis.coverage
Class InterpolationMethod

    Object
      CodeList<InterpolationMethod>
          InterpolationMethod

All Implemented Interfaces:
  Serializable, Comparable<InterpolationMethod>

    @UML(identifier="CV_InterpolationMethod",
         specification=ISO_19123)
    public class InterpolationMethod

extends CodeList<InterpolationMethod>

A list of codes that identify interpolation methods that may be used for evaluating continuous coverages. Evaluation of a continuous coverage involves interpolation between known feature attribute values associated with geometric objects in the domain of the discrete coverage that is provided as control for the continuous coverage. This code list includes 9 interpolation methods. Each is used in the context of specified geometric configurations (table below). Since `InterpolationMethod` is a `CodeList`, it may be extended in an application schema that specifies additional interpolation methods.

Method | Coverage Type | Value object dimension
--- | --- | ---
Nearest Neighbour | Any | Any
Linear | Segmented Curve | 1
Quadratic | Segmented Curve | 1
Cubic | Segmented Curve | 1
Bilinear | Quadrilateral Grid | 2
Biquadratic | Quadrilateral Grid | 2
Bicubic | Quadrilateral Grid | 2
Lost Area | Thiessen Polygon, Hexagonal Grid | 2
Barycentric | TIN | 2

See Also:
  Serialized Form

Field Summary
`static InterpolationMethod` `BARYCENTRIC` Barycentric interpolation.
`static InterpolationMethod` `BICUBIC` Interpolation based on the assumption that feature attribute values vary as a bicubic function of position within the grid cell.
`static InterpolationMethod` `BILINEAR` Interpolation based on the assumption that feature attribute values vary as a bilinear function of position within the grid cell.
`static InterpolationMethod` `BIQUADRATIC` Interpolation based on the assumption that feature attribute values vary as a biquadratic function of position within the grid cell.
`static InterpolationMethod` `CUBIC` Interpolation based on the assumption that feature attribute values vary as a cubic function of distance along a value segment.
`static InterpolationMethod` `LINEAR` Interpolation based on the assumption that feature attribute values vary in proportion to distance along a value segment.
`static InterpolationMethod` `LOST_AREA` Lost area interpolation.
`static InterpolationMethod` `NEAREST_NEIGHBOUR` Generates a feature attribute value at a direct position by assigning it the feature attribute value associated with the nearest domain object in the domain of the coverage.
`static InterpolationMethod` `QUADRATIC` Interpolation based on the assumption that feature attribute values vary as a quadratic function of distance along a value segment.

Method Summary
`CodeList[]` `family()` Returns the list of enumerations of the same kind than this enum.
`static InterpolationMethod` `valueOf(String code)` Returns the InterpolationMethod that matches the given string, or returns a new one if none match it.
`static InterpolationMethod[]` `values()` Returns the list of `InterpolationMethod`s.

Methods inherited from class CodeList
`compareTo, name, ordinal, readResolve, toString`

Methods inherited from class Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

Field Detail

### NEAREST_NEIGHBOUR

    @UML(identifier="Nearest neighbour",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod NEAREST_NEIGHBOUR

  Generates a feature attribute value at a direct position by assigning it the feature attribute value associated with the nearest domain object in the domain of the coverage. Nearest neighbour interpolation extends a discrete coverage to a step function defined on the convex hull of the domain objects in the domain of the coverage. Nearest neighbour interpolation is the only interpolation method described in ISO 19123 that can be used to interpolate attributes that have nominal or ordinal values.

  NOTE: In the case of a discrete point coverage, the "steps" of the step function are the Thiessen polygons generated by the set of points in the domain of the coverage.

### LINEAR

    @UML(identifier="Linear interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod LINEAR

  Interpolation based on the assumption that feature attribute values vary in proportion to distance along a value segment.

  > v = a + b x

  Linear interpolation may be used to interpolate feature attribute values along a line segment connecting any two point value pairs. It may also be used to interpolate feature attribute values at positions along a curve of any form, if the positions are described by values of an arc-length parameter.

  Given two point value pairs (ps, vs) and (pt, vt), where ps is the start point and pt is the end point of a value segment, and vs and vt are the feature attribute values associated with those points, the feature attribute value vi associated with the direct position pi is:

  > vi = vs + (vt - vs) ((pi - ps)/(pt - ps))

### QUADRATIC

    @UML(identifier="Quadratic interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod QUADRATIC

  Interpolation based on the assumption that feature attribute values vary as a quadratic function of distance along a value segment.

  > v = a + b x + c x2

  where a is the value of a feature attribute at the start of a value segment and v is the value of a feature attribute at distance x along the curve from the start. Three point value pairs are needed to provide control values for calculating the coefficients of the function.

### CUBIC

    @UML(identifier="Cubic interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod CUBIC

  Interpolation based on the assumption that feature attribute values vary as a cubic function of distance along a value segment.

  > v = a + b x + c x2 + d x3

  where a is the value of a feature attribute at the start of a value segment and v is the value of a feature attribute at distance x along the curve from the start. Four point value pairs are needed to provide control values for calculating the coefficients of the function.

### BILINEAR

    @UML(identifier="Bilinear interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod BILINEAR

  Interpolation based on the assumption that feature attribute values vary as a bilinear function of position within the grid cell.

### BIQUADRATIC

    @UML(identifier="Biquadratic interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod BIQUADRATIC

  Interpolation based on the assumption that feature attribute values vary as a biquadratic function of position within the grid cell.

### BICUBIC

    @UML(identifier="Bicubic interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod BICUBIC

  Interpolation based on the assumption that feature attribute values vary as a bicubic function of position within the grid cell.

### LOST_AREA

    @UML(identifier="Lost area interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod LOST_AREA

  Lost area interpolation.

### BARYCENTRIC

    @UML(identifier="Barycentric interpolation",
         obligation=CONDITIONAL,
         specification=ISO_19123)
    public static final InterpolationMethod BARYCENTRIC

  Barycentric interpolation.

Method Detail

### values

    public static InterpolationMethod[] values()

  Returns the list of `InterpolationMethod`s.

### family

    public CodeList[] family()

  Returns the list of enumerations of the same kind than this enum.

  Specified by:
    `family` in class `CodeList<InterpolationMethod>`

### valueOf

    public static InterpolationMethod valueOf(String code)

  Returns the InterpolationMethod that matches the given string, or returns a new one if none match it.

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