Ejemplo n.º 1
0
        public Array2DRowRealMatrix subtract(Array2DRowRealMatrix m)
        {
            //MatrixUtils.checkSubtractionCompatible(this, m);

            int rowCount    = getRowDimension();
            int columnCount = getColumnDimension();

            double[][] outData = Java.CreateArray <double[][]>(rowCount, columnCount);// new double[rowCount][columnCount];
            for (int row = 0; row < rowCount; row++)
            {
                double[] dataRow    = data[row];
                double[] mRow       = m.data[row];
                double[] outDataRow = outData[row];
                for (int col = 0; col < columnCount; col++)
                {
                    outDataRow[col] = dataRow[col] - mRow[col];
                }
            }

            return(new Array2DRowRealMatrix(outData, false));
        }
Ejemplo n.º 2
0
        public Array2DRowRealMatrix multiply(Array2DRowRealMatrix m)
        {
            //MatrixUtils.checkMultiplicationCompatible(this, m);

            int nRows = getRowDimension();
            int nCols = m.getColumnDimension();
            int nSum  = getColumnDimension();

            double[][] outData = Java.CreateArray <double[][]>(nRows, nCols);// new double[nRows][nCols];
            // Will hold a column of "m".
            double[]   mCol  = new double[nSum];
            double[][] mData = m.data;

            // Multiply.
            for (int col = 0; col < nCols; col++)
            {
                // Copy all elements of column "col" of "m" so that
                // will be in contiguous memory.
                for (int mRow = 0; mRow < nSum; mRow++)
                {
                    mCol[mRow] = mData[mRow][col];
                }

                for (int row = 0; row < nRows; row++)
                {
                    double[] dataRow = data[row];
                    double   sum     = 0;
                    for (int i = 0; i < nSum; i++)
                    {
                        sum += dataRow[i] * mCol[i];
                    }
                    outData[row][col] = sum;
                }
            }

            return(new Array2DRowRealMatrix(outData, false));
        }
Ejemplo n.º 3
0
        /**
         * Compute the outer product.
         *
         * @param v Vector with which outer product should be computed.
         * @return the matrix outer product between this instance and {@code v}.
         */
        public virtual RealMatrix outerProduct(RealVector v)
        {
            //throw new NotImplementedException();
            int        m = getDimension();
            int        n = v.getDimension();
            RealMatrix product;

            if (v is SparseRealVector || this is SparseRealVector)
            {
                product = new OpenMapRealMatrix(m, n);
            }
            else
            {
                product = new Array2DRowRealMatrix(m, n);
            }
            for (int i = 0; i < m; i++)
            {
                for (int j = 0; j < n; j++)
                {
                    product.setEntry(i, j, getEntry(i) * v.getEntry(j));
                }
            }
            return(product);
        }
Ejemplo n.º 4
0
        public LUDecomposition(Array2DRowRealMatrix matrix, double singularityThreshold)
        {
            //     if (!matrix.isSquare()) {
            //    throw new NonSquareMatrixException(matrix.getRowDimension(),
            //                                       matrix.getColumnDimension());
            //}

            int m = matrix.getColumnDimension();

            lu      = matrix.getData();
            pivot   = new int[m];
            cachedL = null;
            cachedU = null;
            cachedP = null;

            // Initialize permutation array and parity
            for (int row = 0; row < m; row++)
            {
                pivot[row] = row;
            }
            even     = true;
            singular = false;

            // Loop over columns
            for (int col = 0; col < m; col++)
            {
                // upper
                for (int row = 0; row < col; row++)
                {
                    double[] luRow = lu[row];
                    double   sum   = luRow[col];
                    for (int i = 0; i < row; i++)
                    {
                        sum -= luRow[i] * lu[i][col];
                    }
                    luRow[col] = sum;
                }

                // lower
                int    max     = col; // permutation row
                double largest = double.NegativeInfinity;
                for (int row = col; row < m; row++)
                {
                    double[] luRow = lu[row];
                    double   sum   = luRow[col];
                    for (int i = 0; i < col; i++)
                    {
                        sum -= luRow[i] * lu[i][col];
                    }
                    luRow[col] = sum;

                    // maintain best permutation choice
                    if (Math.Abs(sum) > largest)
                    {
                        largest = Math.Abs(sum);
                        max     = row;
                    }
                }

                // Singularity check
                if (Math.Abs(lu[max][col]) < singularityThreshold)
                {
                    singular = true;
                    return;
                }

                // Pivot if necessary
                if (max != col)
                {
                    double   tmp   = 0;
                    double[] luMax = lu[max];
                    double[] luCol = lu[col];
                    for (int i = 0; i < m; i++)
                    {
                        tmp      = luMax[i];
                        luMax[i] = luCol[i];
                        luCol[i] = tmp;
                    }
                    int temp = pivot[max];
                    pivot[max] = pivot[col];
                    pivot[col] = temp;
                    even       = !even;
                }

                // Divide the lower elements by the "winning" diagonal elt.
                double luDiag = lu[col][col];
                for (int row = col + 1; row < m; row++)
                {
                    lu[row][col] /= luDiag;
                }
            }
        }
Ejemplo n.º 5
0
 public LUDecomposition(Array2DRowRealMatrix matrix) : this(matrix, DEFAULT_TOO_SMALL)
 {
 }