Class KDTreePositions

java.lang.Object
net.imglib2.kdtree.KDTreePositions
Direct Known Subclasses:
KDTreePositions.Flat, KDTreePositions.Nested
public abstract class KDTreePositions extends Object
Stores the positions of the nodes in a KDTree and provides access to them.

Currently, there are two implementations:

  • KDTreePositions.Nested stores the positions as a double[][] where positions[d][i] is dimension d of the i-th point. This allows for a total of 2^31-8 nodes but doesn't keep the positions contiguous in memory.
  • KDTreePositions.Flat stores the positions as a double[] where positions[d + i*n] is dimension d of the i-th point, with n the number of dimensions. This means that the positions are contiguous in memory but the number of nodes is limited to (2^31-8)/n.
asNestedArray() returns positions in nested double[][] (which is created if class is KDTreePositions.Flat). asFlatArray() returns flat double[] if class is KDTreePositions.Flat, otherwise null.

  • Field Details

    • numDimensions

      final int numDimensions

    • numPoints

      final int numPoints

    • boundingBox

      private volatile RealInterval boundingBox

  • Constructor Details

    • KDTreePositions

      KDTreePositions(int numDimensions, int numPoints)

  • Method Details

    • get

      public abstract double get(int i, int d)
      Get the coordinates of the node i in dimension d.
      Returns:
      the coordinate

    • asFlatArray

      public abstract double[] asFlatArray()
      Get positions of points in the tree as a flat double[] array where positions[d + i*n] is dimension d of the i-th point.

      For serialisation and usage by the tree.

      Internal storage may be a NESTED double[][] array. In this case, flatPositions() returns null.

    • asNestedArray

      public abstract double[][] asNestedArray()
      Get positions of points in the tree as a nested double[][] array where positions[d][i] is dimension d of the i-th point.

      For serialisation and usage by the tree.

      Internal storage may be flattened into single double[] array. In this case, the nested double[][] array is created here.

    • createBoundingBox

      abstract RealInterval createBoundingBox()

    • layout

      public abstract KDTreePositions.PositionsLayout layout()
      Get the internal layout of positions.

      Positions are stored in either FLAT or NESTED layout. With NESTED layout, positions are stored as a nested double[][] array where positions[d][i] is dimension d of the i-th point. With FLAT layout, positions are stored as a flat double[] array, where positions[d + i*n] is dimension d of the i-th point, with n the number of dimensions.

    • numDimensions

      public int numDimensions()
      Returns:
      dimensionality of points in the tree

    • numPoints

      public int numPoints()
      Returns:
      number of points in the tree

    • createNested

      public static KDTreePositions createNested(double[][] positions)
      Create KDTreePositions with NESTED layout().

    • createFlat

      public static KDTreePositions createFlat(double[] positions, int numDimensions)
      Create KDTreePositions with FLAT layout().