/// <summary>
/// Creates a square matrix matrix with random data.
/// </summary>
///
public static T[][] Random <T>(int size, IRandomNumberGenerator <T> generator,
bool symmetric = false, T[][] result = null)
{
if (result == null)
{
result = Jagged.Create <T>(size, size);
}
if (!symmetric)
{
for (int i = 0; i < size; i++)
{
result[i] = generator.Generate(size);
}
}
else
{
for (int i = 0; i < size; i++)
{
T[] row = generator.Generate(size / 2, result[i]);
for (int start = 0, end = size - 1; start < size / 2; start++, end--)
{
row[end] = row[start];
}
}
}
return(result);
}
public static T[][] Diagonal <T>(T[][][] blocks)
{
int rows = 0;
int cols = 0;
for (int i = 0; i < blocks.Length; i++)
{
rows += blocks[i].Rows();
cols += blocks[i].Columns();
}
var result = Jagged.Create <T>(rows, cols);
int currentRow = 0;
int currentCol = 0;
for (int i = 0; i < blocks.Length; i++)
{
for (int r = 0; r < blocks[i].Length; r++)
{
for (int c = 0; c < blocks[i][r].Length; c++)
{
result[currentRow + r][currentCol + c] = blocks[i][r][c];
}
}
currentRow = blocks[i].Length;
currentCol = blocks[i][0].Length;
}
return(result);
}
/// <summary>
/// Creates a matrix with uniformly distributed random data.
/// </summary>
///
public static int[][] Random(int size, int min, int max, bool symmetric = false, int[][] result = null)
{
if (result == null)
{
result = Jagged.Create <int>(size, size);
}
var random = Accord.Math.Random.Generator.Random;
if (symmetric)
{
for (int i = 0; i < size; i++)
{
for (int j = i; j < size; j++)
{
result[i][j] = result[j][i] = (int)random.Next((int)min, (int)max);
}
}
}
else
{
for (int i = 0; i < size; i++)
{
for (int j = i; j < size; j++)
{
result[i][j] = (int)random.Next((int)min, (int)max);
}
}
}
return(result);
}
public static Array Create(Type elementType, params int[] shape)
{
int s = shape[0];
if (shape.Length == 1)
{
return(Array.CreateInstance(elementType, s));
}
else
{
int[] rest = shape.Get(1, 0);
if (s == 0)
{
Array dummy = Array.CreateInstance(elementType, rest);
Array container = Array.CreateInstance(dummy.GetType(), 0);
return(container);
}
else
{
Array first = Jagged.Create(elementType, rest);
Array container = Array.CreateInstance(first.GetType(), s);
container.SetValue(first, 0);
for (int i = 1; i < container.Length; i++)
{
container.SetValue(Create(elementType, rest), i);
}
return(container);
}
}
}
/// <summary>
/// Creates a matrix with uniformly distributed random data.
/// </summary>
///
public static decimal[][] Random(int size, decimal min, decimal max, bool symmetric = false, decimal[][] result = null)
{
if (result == null)
{
result = Jagged.Create <decimal>(size, size);
}
var random = Accord.Math.Random.Generator.Random;
if (symmetric)
{
for (int i = 0; i < size; i++)
{
for (int j = i; j < size; j++)
{
result[i][j] = result[j][i] = (decimal)random.NextDouble() * (max - min) + min;
}
}
}
else
{
for (int i = 0; i < size; i++)
{
for (int j = i; j < size; j++)
{
result[i][j] = (decimal)random.NextDouble() * (max - min) + min;
}
}
}
return(result);
}
/// <summary>
/// Sets a region of a matrix to the given values.
/// </summary>
///
/// <param name="destination">The matrix where elements will be set.</param>
/// <param name="value">The matrix of values to which matrix elements will be set.</param>
/// <param name="startRow">Starting row index</param>
/// <param name="endRow">End row index</param>
/// <param name="startCol">Starting column index</param>
/// <param name="endCol">End column index</param>
///
public static void Set <T>(this T[][] destination, T value, int startRow, int endRow, int startCol, int endCol)
{
var values = Jagged.Create <T>(destination.Rows(), destination.Columns(), value);
var rowIndices = Accord.Math.Vector.Range(startRow, end(endRow, destination.Rows()));
var columnIndices = Accord.Math.Vector.Range(startCol, end(endCol, destination.Columns()));
set(destination, rowIndices, columnIndices, values, rowIndices, columnIndices);
}
public static Array CreateAs(Array matrix, Type type)
{
int[] outputShape = Matrix.GetShape(matrix, type);
#if !NETSTANDARD1_4
// multidimensional or jagged -> jagged
return(Jagged.Create(elementType: type.GetInnerMostType(), shape: outputShape, value: type.GetDefaultValue()));
#else
return(Jagged.Create(elementType: type.GetInnerMostType(), shape: outputShape, value: 0));
#endif
}
/// <summary>
/// Creates a rows-by-cols matrix with random data.
/// </summary>
///
public static T[][] Random <T>(int rows, int cols,
IRandomNumberGenerator <T> generator, T[][] result = null)
{
if (result == null)
{
result = Jagged.Create <T>(rows, cols);
}
for (int i = 0; i < rows; i++)
{
result[i] = generator.Generate(cols);
}
return(result);
}
/// <summary>
/// Creates a matrix with uniformly distributed random data.
/// </summary>
///
public static int[][] Random(int rows, int columns, int min, int max, int[][] result = null)
{
if (result == null)
{
result = Jagged.Create <int>(rows, columns);
}
var random = Accord.Math.Random.Generator.Random;
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < columns; j++)
{
result[i][j] = (int)random.Next((int)min, (int)max);
}
}
return(result);
}
/// <summary>
/// Creates a matrix with uniformly distributed random data.
/// </summary>
///
public static decimal[][] Random(int rows, int columns, decimal min, decimal max, decimal[][] result = null)
{
if (result == null)
{
result = Jagged.Create <decimal>(rows, columns);
}
var random = Accord.Math.Random.Generator.Random;
for (int i = 0; i < rows; i++)
{
for (int j = 0; j < columns; j++)
{
result[i][j] = (decimal)random.NextDouble() * (max - min) + min;
}
}
return(result);
}
/// <summary>
/// Sets a region of a matrix to the given values.
/// </summary>
///
/// <param name="destination">The matrix where elements will be set.</param>
/// <param name="value">The matrix of values to which matrix elements will be set.</param>
/// <param name="startRow">Starting row index</param>
/// <param name="endRow">End row index</param>
/// <param name="columnIndices">Array of column indices</param>
///
public static void Set <T>(this T[][] destination, T value, int startRow, int endRow, int[] columnIndices)
{
T[][] source = Jagged.Create(destination.Rows(), destination.Columns(), value);
Set(destination, source, startRow, endRow, columnIndices);
}
public static T[][] Diagonal <T>(int rows, int cols, T[] values)
{
return(Diagonal(rows, cols, values, Jagged.Create <T>(rows, cols)));
}
public static T[][] Diagonal <T>(T[] values)
{
return(Diagonal(values, Jagged.Create <T>(values.Length, values.Length)));
}
public static T[][] Diagonal <T>(int size, T value)
{
return(Diagonal(size, value, Jagged.Create <T>(size, size)));
}
/// <summary>
/// Sets a region of a matrix to the given values.
/// </summary>
///
/// <param name="destination">The matrix where elements will be set.</param>
/// <param name="value">The value to which matrix elements will be set.</param>
///
public static void Set <T>(this T[][] destination, T value)
{
Set(destination, Jagged.Create(destination.Rows(), destination.Columns(), value));
}
public static double[][] KHot(bool[][] mask, int columns)
{
return(KHot(mask, Jagged.Create <double>(mask.Length, columns)));
}
public static double[][] KHot(int[][] indices, int columns)
{
return(KHot(indices, Jagged.Create <double>(indices.Length, columns)));
}
public static T[][] KHot <T>(int[][] indices, int columns)
{
return(KHot <T>(indices, Jagged.Create <T>(indices.Length, columns)));
}
public static T[][] OneHot <T>(bool[] mask)
{
return(OneHot <T>(mask, Jagged.Create <T>(mask.Length, 2)));
}
/// <summary>
/// Sets a region of a matrix to the given values.
/// </summary>
///
/// <param name="destination">The matrix where elements will be set.</param>
/// <param name="value">The matrix of values to which matrix elements will be set.</param>
/// <param name="rowIndices">Array of row indices</param>
/// <param name="columnIndices">Array of column indices</param>
///
public static void Set <T>(this T[][] destination, T value, int[] rowIndices, int[] columnIndices)
{
var values = Jagged.Create <T>(destination.Rows(), destination.Columns(), value);
set(destination, rowIndices, columnIndices, values, rowIndices, columnIndices);
}
/// <summary>
/// Sets a region of a matrix to the given values.
/// </summary>
///
/// <param name="destination">The matrix where elements will be set.</param>
/// <param name="value">The matrix of values to which matrix elements will be set.</param>
/// <param name="rowIndices">Array of row indices</param>
/// <param name="startColumn">Start column index</param>
/// <param name="endColumn">End column index</param>
///
public static void Set <T>(this T[][] destination, T value, int[] rowIndices, int startColumn, int endColumn)
{
Set(destination, Jagged.Create(destination.Rows(), destination.Columns(), value), rowIndices, startColumn, endColumn);
}
/// <summary>
/// Transforms a vector into a matrix of given dimensions.
/// </summary>
///
public static T[][] Reshape <T>(T[] array, int rows, int cols, MatrixOrder order = MatrixOrder.Default)
{
return(Jagged.Reshape(array, rows, cols, Jagged.Create <T>(rows, cols), order));
}