Class DenseVector

java.lang.Object
org.la4j.Vector
org.la4j.vector.DenseVector
All Implemented Interfaces:
Iterable<Double>
Direct Known Subclasses:
BasicVector
public abstract class DenseVector extends Vector
A dense vector. A vector represents an array of elements. It can be re-sized. A dense data structure usually stores data in an underlying array. Zero elements take up memory space. If you want a data structure that will not have zero elements take up memory space, try a sparse structure. However, fetch/store operations on dense data structures only take O(1) time, instead of the O(log n) time on sparse structures.

  • Constructor Details

    • DenseVector

      public DenseVector(int length)

  • Method Details

    • zero

      public static DenseVector zero(int length)
      Creates a zero DenseVector of the given length.

    • constant

      public static DenseVector constant(int length, double value)
      Creates a constant DenseVector of the given length with the given value.

    • unit

      public static DenseVector unit(int length)
      Creates an unit DenseVector of the given length.

    • random

      public static DenseVector random(int length, Random random)
      Creates a random DenseVector of the given length with the given Random.

    • fromArray

      public static DenseVector fromArray(double[] array)
      Creates a new DenseVector from the given array w/o copying the underlying array.

    • fromCSV

      public static DenseVector fromCSV(String csv)
      Parses DenseVector from the given CSV string.
      Parameters:
      csv - the CSV string representing a vector
      Returns:
      a parsed vector

    • fromMatrixMarket

      public static DenseVector fromMatrixMarket(String mm)
      Parses DenseVector from the given Matrix Market string.
      Parameters:
      mm - the string in Matrix Market format
      Returns:
      a parsed vector

    • fromCollection

      public static DenseVector fromCollection(Collection<? extends Number> list)
      Creates new DenseVector from
      Parameters:
      list - list containing doubles
      Returns:
      new vector from given double list

    • fromMap

      public static DenseVector fromMap(Map<Integer, ? extends Number> map, int length)
      Creates new DenseVector from index-value map
      Parameters:
      map - index-value map
      length - vector length
      Returns:
      created vector

    • apply

      public <T> T apply(VectorOperation<T> operation)
      Description copied from class: Vector
      Pipes this vector to a given operation.
      Specified by:
      apply in class Vector
      Type Parameters:
      T - the result type
      Parameters:
      operation - the vector operation (an operation that take vector and returns T)
      Returns:
      the result of an operation applied to this vector

    • apply

      public <T> T apply(VectorVectorOperation<T> operation, Vector that)
      Description copied from class: Vector
      Pipes this vector to a given operation.
      Specified by:
      apply in class Vector
      Type Parameters:
      T - the result type
      Parameters:
      operation - the vector-vector operation (an operation that takes two vectors and returns T)
      that - the right hand vector for the given operation
      Returns:
      the result of an operation applied to this and that vector

    • apply

      public <T> T apply(VectorMatrixOperation<T> operation, Matrix that)
      Description copied from class: Vector
      Pipes this vector to a given operation.
      Specified by:
      apply in class Vector
      Type Parameters:
      T - the result type
      Parameters:
      operation - the vector-matrix operation (an operation that takes vector and matrix and returns T)
      that - the right hand matrix for the given operation
      Returns:
      the result of an operation applied to this vector and that matrix

    • toArray

      public abstract double[] toArray()
      Converts this dense vector to a double array.
      Returns:
      an array representation of this vector

    • toRowMatrix

      public Matrix toRowMatrix()
      Description copied from class: Vector
      Converts this vector to matrix with only one row.
      Specified by:
      toRowMatrix in class Vector
      Returns:
      the row matrix

    • toColumnMatrix

      public Matrix toColumnMatrix()
      Description copied from class: Vector
      Converts this vector to matrix with only one column.
      Specified by:
      toColumnMatrix in class Vector
      Returns:
      the column matrix

    • toDiagonalMatrix

      public Matrix toDiagonalMatrix()
      Description copied from class: Vector
      Converts this vector to a diagonal matrix.
      Specified by:
      toDiagonalMatrix in class Vector
      Returns:
      a diagonal matrix

    • toMatrixMarket

      public String toMatrixMarket(NumberFormat formatter)
      Description copied from class: Vector
      Converts this vector into the string in Matrix Market format using the given formatter;
      Specified by:
      toMatrixMarket in class Vector
      Parameters:
      formatter - the number formater
      Returns:
      a Matrix Market string representing this vector