public static Object Where(this Double[,] matrix, Function f)
{
var result = new List <Double>();
var args = new Object[4];
var rows = matrix.GetRows();
var columns = matrix.GetColumns();
for (int i = 0, k = 0; i < rows; i++)
{
for (var j = 0; j < columns; j++, k++)
{
var value = matrix[i, j];
args[0] = value;
args[1] = (Double)k;
args[2] = (Double)i;
args[3] = (Double)j;
if (f(args).ToBoolean())
{
result.Add(value);
}
}
}
return(result.ToMatrix());
}
public static Double[,] Multiply(this Double[,] a, Double[,] b)
{
var rows = a.GetRows();
var cols = b.GetColumns();
var length = a.GetColumns();
if (length == b.GetRows())
{
var result = new Double[rows, cols];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
var value = 0.0;
for (var k = 0; k < length; k++)
{
value += a[i, k] * b[k, j];
}
result[i, j] = value;
}
}
return(result);
}
return(null);
}
/// <summary>
/// Converts the given matrix to a JSON string.
/// </summary>
/// <param name="matrix">The matrix to represent.</param>
/// <returns>The JSON representation.</returns>
public static String AsJson(Double[,] matrix)
{
var sb = StringBuilderPool.Pull();
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
sb.Append('[');
for (var i = 0; i < rows; i++)
{
if (i > 0)
{
sb.Append(", ");
}
sb.Append('[');
for (var j = 0; j < cols; j++)
{
if (j > 0)
{
sb.Append(", ");
}
sb.Append(This(matrix[i, j]));
}
sb.Append(']');
}
sb.Append(']');
return(sb.Stringify());
}
public static Double ToNumber(this Double[,] matrix)
{
if (matrix.GetRows() == 1 && matrix.GetColumns() == 1)
{
return(matrix[0, 0]);
}
return(Double.NaN);
}
public static Boolean Fits(this Double[,] a, Double[,] b)
{
var rowsA = a.GetRows();
var rowsB = b.GetRows();
var colsA = a.GetColumns();
var colsB = b.GetColumns();
return(rowsA == rowsB && colsA == colsB);
}
public static void SetValue(this Double[,] matrix, Int32 row, Int32 col, Double value)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
if (row >= 0 && row < rows && col >= 0 && col < cols)
{
matrix[row, col] = value;
}
}
public static Double GetValue(this Double[,] matrix, Int32 row, Int32 col)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
if (row >= 0 && row < rows && col >= 0 && col < cols)
{
return(matrix[row, col]);
}
return(0.0);
}
public static Double[,] Identity(this Double[,] matrix)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var result = new Double[rows, cols];
var length = Math.Min(rows, cols);
for (var i = 0; i < length; i++)
{
result[i, i] = 1.0;
}
return(result);
}
public static Object Reduce(this Double[,] matrix, Func <Double, Double, Double> reducer)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
if (rows == 1 && cols == 1)
{
return(matrix[0, 0]);
}
else if (rows == 1)
{
var element = matrix[0, 0];
for (var i = 1; i < cols; i++)
{
element = reducer.Invoke(element, matrix[0, i]);
}
return(element);
}
else if (cols == 1)
{
var element = matrix[0, 0];
for (var i = 1; i < rows; i++)
{
element = reducer.Invoke(element, matrix[i, 0]);
}
return(element);
}
else
{
var result = new Double[rows, 1];
for (var i = 0; i < rows; i++)
{
var element = matrix[i, 0];
for (var j = 1; j < cols; j++)
{
element = reducer.Invoke(element, matrix[i, j]);
}
result[i, 0] = element;
}
return(result);
}
}
public static Double[,] Transpose(this Double[,] matrix)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var result = new Double[cols, rows];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[j, i] = matrix[i, j];
}
}
return(result);
}
public static Double[,] ForEach(this Double[,] matrix, Func <Double, Double> apply)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var result = new Double[rows, cols];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = apply(matrix[i, j]);
}
}
return(result);
}
public static Double[,] Pow(this Double value, Double[,] matrix)
{
var result = matrix.Fill(value);
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = Math.Pow(result[i, j], matrix[i, j]);
}
}
return(result);
}
public static Double Abs(Double[,] matrix)
{
var sum = 0.0;
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
sum += matrix[i, j] * matrix[i, j];
}
}
return(Math.Sqrt(sum));
}
public static Boolean AllTrue(this Double[,] matrix)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var res = true;
for (var i = 0; i < rows; i++)
{
for (var j = 0; res && j < cols; j++)
{
res = matrix[i, j].ToBoolean();
}
}
return(res);
}
public static Double[,] Multiply(this Double[,] a, Double b)
{
var rows = a.GetRows();
var cols = a.GetColumns();
var result = new Double[rows, cols];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = a[i, j] * b;
}
}
return(result);
}
public static List <Double> ToList(this Double[,] matrix)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var list = new List <Double>(rows * cols);
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
list.Add(matrix[i, j]);
}
}
return(list);
}
public static Double[,] Fill(this Double[,] matrix, Double value)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var result = new Double[rows, cols];
var length = Math.Min(rows, cols);
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = value;
}
}
return(result);
}
public static Boolean HasAny(this Double[,] matrix, Predicate <Double> check)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
if (check(matrix[i, j]))
{
return(true);
}
}
}
return(false);
}
public static Boolean TryGetIndices(this Double[,] matrix, Object[] arguments, out Int32 row, out Int32 col)
{
var rows = matrix.GetRows();
var cols = matrix.GetColumns();
var n = 0;
row = -1;
col = -1;
if (arguments.Length == 1 && arguments[0].TryGetIndex(out n))
{
col = n % cols;
row = n / cols;
}
else if (arguments.Length == 2 && arguments[0].TryGetIndex(out row) && arguments[1].TryGetIndex(out col))
{
}
return(row >= 0 && col >= 0 && row < rows && col < cols);
}
public static Double[,] Or(this Double[,] a, Double[,] b)
{
if (a.Fits(b))
{
var rows = a.GetRows();
var cols = a.GetColumns();
var result = new Double[rows, cols];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = (a[i, j].ToBoolean() || b[i, j].ToBoolean()).ToNumber();
}
}
return(result);
}
return(null);
}
public static Object Map(this Double[,] matrix, Function f)
{
var result = new Dictionary <String, Object>();
var args = new Object[4];
var rows = matrix.GetRows();
var columns = matrix.GetColumns();
for (int i = 0, k = 0; i < rows; i++)
{
for (var j = 0; j < columns; j++, k++)
{
args[0] = matrix[i, j];
args[1] = (Double)k;
args[2] = (Double)i;
args[3] = (Double)j;
result[k.ToString()] = f(args);
}
}
return(result);
}
public static Double[,] IsGreaterOrEqual(this Double[,] a, Double[,] b)
{
if (a.Fits(b))
{
var rows = a.GetRows();
var cols = a.GetColumns();
var result = new Double[rows, cols];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = (a[i, j] >= b[i, j]).ToNumber();
}
}
return(result);
}
return(null);
}
public static Double[,] Pow(this Double[,] a, Double[,] b)
{
if (a.Fits(b))
{
var rows = a.GetRows();
var cols = a.GetColumns();
var result = new Double[rows, cols];
for (var i = 0; i < rows; i++)
{
for (var j = 0; j < cols; j++)
{
result[i, j] = Math.Pow(a[i, j], b[i, j]);
}
}
return(result);
}
return(null);
}
public static Object Reduce(this Double[,] matrix, Function f, Object start)
{
var args = new Object[5];
var result = start;
var rows = matrix.GetRows();
var columns = matrix.GetColumns();
for (int i = 0, k = 0; i < rows; i++)
{
for (var j = 0; j < columns; j++, k++)
{
args[0] = result;
args[1] = matrix[i, j];
args[2] = (Double)k;
args[3] = (Double)i;
args[4] = (Double)j;
result = f(args);
}
}
return(result);
}
public static Boolean IsSquare(this Double[,] matrix)
{
return(matrix.GetColumns() == matrix.GetRows());
}