Package dsa

Class SparseMatrix

java.lang.Object
dsa.SparseMatrix
public class SparseMatrix extends Object
A data type to represent an m x n sparse matrix.

  • Constructor Summary

    Constructors
    Constructor
    Description
    SparseMatrix(int m, int n)
    Constructs an m x n dimensional zero matrix.

  • Method Summary

    Modifier and Type
    Method
    Description
    double
    get(int i, int j)
    Returns the entry in this matrix at row i and column j.
    static void
    main(String[] args)
    Unit tests the data type.
    int
    nCols()
    Returns the number of columns in this matrix.
    int
    nRows()
    Returns the number of rows in this matrix.
    SparseMatrix
    plus(SparseMatrix other)
    Returns the sum of this matrix and other.
    void
    put(int i, int j, double value)
    Sets the entry at row i and column j in this matrix to value.
    int
    size()
    Returns the number of nonzero entries in this matrix.
    SparseVector
    times(SparseVector x)
    Returns the product of this matrix and the vector x.
    String
    toString()
    Returns a string representation of this matrix.

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • SparseMatrix

      public SparseMatrix(int m, int n)
      Constructs an m x n dimensional zero matrix.
      Parameters:
      m - number of rows in the matrix.
      n - number of columns in the matrix.

  • Method Details

    • nRows

      public int nRows()
      Returns the number of rows in this matrix.
      Returns:
      the number of rows in this matrix.

    • nCols

      public int nCols()
      Returns the number of columns in this matrix.
      Returns:
      the number of columns in this matrix.

    • size

      public int size()
      Returns the number of nonzero entries in this matrix.
      Returns:
      the number of nonzero entries in this matrix.

    • put

      public void put(int i, int j, double value)
      Sets the entry at row i and column j in this matrix to value.
      Parameters:
      i - row index.
      j - column index.
      value - the value.

    • get

      public double get(int i, int j)
      Returns the entry in this matrix at row i and column j.
      Parameters:
      i - row index.
      j - column index.
      Returns:
      the entry in this matrix at row i and column j.

    • plus

      public SparseMatrix plus(SparseMatrix other)
      Returns the sum of this matrix and other.
      Parameters:
      other - the other matrix.
      Returns:
      the sum of this matrix and other.

    • times

      public SparseVector times(SparseVector x)
      Returns the product of this matrix and the vector x.
      Parameters:
      x - the vector.
      Returns:
      the product of this matrix and the vector x.

    • toString

      public String toString()
      Returns a string representation of this matrix.
      Overrides:
      toString in class Object
      Returns:
      a string representation of this matrix.

    • main

      public static void main(String[] args)
      Unit tests the data type.
      Parameters:
      args - the command-line arguments.