Package com.imsl.math

Class ComplexSparseMatrix.SparseArray

java.lang.Object
com.imsl.math.ComplexSparseMatrix.SparseArray
All Implemented Interfaces:
Serializable
Enclosing class:
ComplexSparseMatrix
public static class ComplexSparseMatrix.SparseArray extends Object implements Serializable
The SparseArray class uses public fields to hold the data for a sparse matrix in the Java Sparse Array format. This format came about as a means for storing sparse matrices in Java. In this format, a sparse matrix is represented by two arrays of arrays. One array contains the references to the nonzero value arrays for each row of the sparse matrix. The other contains the references to the associated column index arrays.

As an example, consider the following complex sparse matrix: $$ A=\begin{pmatrix} 10.0-3.0i & 0.0 & 0.0 & 0.0 & 0.0 & 0.0 \\ 0.0 & 10.0 & -3.0+2.0i & -1.0-1.0i & 0.0 & 0.0 \\ 0.0 & 0.0 & 15.0+5.0i & 0.0 & 0.0 & 0.0 \\ -2.0 & 0.0 & 0.0 & 10.0+1.0i & -1.0-2.0i & 0.0 \\ -1.0 & 0.0 & 0.0 & -5.0+7.0i & 1.0-3.0i & -3.0 \\ -1.0+4.0i & -2.0+1.0i & 0.0 & 0.0 & 0.0 & 6.0-5.0i \end{pmatrix} $$ In SparseArray, this matrix can be represented by the two jagged arrays, values and index, where values refers to the nonzero entries in A and index to the column indices: 

            Complex values[][] = {
                        {new Complex(10.0, -3.0)},
                        {new Complex(10.0, 0.0), new Complex(-3.0, 2.0), new Complex(-1.0,-1.0)},
                        {new Complex(15.0, 5.0)},
                        {new Complex(-2.0, 0.0), new Complex(10.0, 1.0), new Complex(-1.0, -2.0)},
                        {new Complex(-1.0, 0.0), new Complex(-5.0, 7.0), new Complex(1.0, -3.0),
           new Complex(-3.0, 0.0)},
          {new Complex(-1.0, 4.0), new Complex(-2.0, 1.0), new Complex(6.0, -5.0)}
                }

                int index[][] = {
          {0}, 
          {1, 2, 3},
          {2},
          {0, 3, 4},
          {0, 3, 4, 5},
          {0, 1, 5}
      }

See Also:

  • Field Details

    • numberOfRows

      public int numberOfRows
      Number of rows in the matrix.

    • numberOfColumns

      public int numberOfColumns
      Number of columns in the matrix.

    • numberOfNonZeros

      public long numberOfNonZeros
      Number of nonzeros in the matrix.

    • index

      public int[][] index
      Jagged array containing column indices. The length of this array equals numberOfRows. The length of each row equals the number of nonzeros in that row of the sparse matrix.

    • values

      public Complex[][] values
      Jagged array containing sparse array values. This array must have the same shape as index.

  • Constructor Details

    • SparseArray

      public SparseArray()