/// <summary>
/// Sorts the given Matrix by the specified row or column selector and returns the new Matrix
/// along with the original indices.
/// </summary>
/// <param name="source">The Matrix</param>
/// <param name="keySelector">Property selector to sort by.</param>
/// <param name="t">Specifies whether to sort horizontally or vertically.</param>
/// <param name="ascending">Determines whether to sort ascending or descending (Default: True)</param>
/// <param name="indices">Vector of <paramref name="t"/> indices in the original Matrix before the sort operation.</param>
/// <returns>New Matrix and Vector of original indices.</returns>
public static Matrix Sort(Matrix source, Func <Vector, double> keySelector, VectorType t, bool ascending, out Vector indices)
{
int max = (t == VectorType.Row ? source.Rows : source.Cols);
indices = Vector.Zeros(max);
List <Vector> vects = new List <Vector>(max);
IEnumerable <Vector> arrays = (t == VectorType.Row ? source.GetRows() : source.GetCols());
KeyValuePair <Vector, int>[] sort = (ascending ?
arrays.Select((i, v) => new KeyValuePair <Vector, int>(i, v))
.OrderBy(o => keySelector(o.Key))
:
arrays.Select((i, v) => new KeyValuePair <Vector, int>(i, v))
.OrderByDescending(o => keySelector(o.Key))).ToArray();
indices = sort.Select(s => s.Value).ToVector();
return(sort.Select(s => s.Key).ToMatrix(t));
}
/// <summary>
/// Unshapes the given Matrix into a Vector form along the <paramref name="dimensionType"/> axis.
/// <para>Reads from the source Matrix and stacks from right to left when <paramref name="dimensionType"/> equals 'Col' otherwise uses a bottom up approach.</para>
/// </summary>
/// <param name="m">The Matrix to act on.</param>
/// <param name="dimensionType">Type of the dimension to use when unrolling the Matrix.</param>
/// <returns>Matrix.</returns>
public static Vector Unshape(Matrix m, VectorType dimensionType = VectorType.Col)
{
return(Vector.Combine((dimensionType == VectorType.Col ? m.GetCols().ToArray() : m.GetRows().ToArray())));
}
/// <summary>
/// Returns a vector of the median values for each row or column.
/// </summary>
/// <param name="source">Matrix.</param>
/// <param name="t">VectorType.</param>
/// <returns></returns>
public static Vector Median(Matrix source, VectorType t = VectorType.Col)
{
var vectors = (t == VectorType.Row ? source.GetCols() : source.GetRows());
return(vectors.Select(s => s.Median()).ToVector());
}
/// <summary>
/// Slices the input matrix using starting and stopping positions.
/// </summary>
/// <param name="m">Source matrix.</param>
/// <param name="minIndex">Minimum index to slice from.</param>
/// <param name="maxIndex">Maximum index to slice.</param>
/// <param name="t"></param>
/// <returns></returns>
public static Matrix Slice(this Matrix m, int minIndex, int maxIndex, VectorType t = VectorType.Row)
{
IEnumerable <Vector> array = (t == VectorType.Row ? m.GetRows() : m.GetCols());
return(array.Skip(minIndex).Take((maxIndex - minIndex) + 1).ToMatrix(t));
}
/// <summary>
/// Slices the input matrix using starting and stopping positions.
/// </summary>
/// <param name="m">Source matrix.</param>
/// <param name="minIndex">Minimum index to slice from.</param>
/// <param name="maxIndex">Maximum index to slice.</param>
/// <param name="t"></param>
/// <returns></returns>
public static Matrix Slice(this Matrix m, int minIndex, int maxIndex, VectorType t = VectorType.Row)
{
var array = t == VectorType.Row ? m.GetRows() : m.GetCols();
return(array.Skip(minIndex).Take(maxIndex - minIndex + 1).ToMatrix(t));
}
/// <summary>
/// Unshapes the given Matrix into a Vector form along the <paramref name="dimensionType"/> axis.
/// <para>Reads from the source Matrix and stacks from right to left when <paramref name="dimensionType"/> equals 'Col' otherwise uses a bottom up approach.</para>
/// </summary>
/// <param name="m">The Matrix to act on.</param>
/// <param name="dimensionType">Type of the dimension to use when unrolling the Matrix.</param>
/// <returns>Matrix.</returns>
public static Vector Unshape(Matrix m, VectorType dimensionType = VectorType.Col)
{
return Vector.Combine((dimensionType == VectorType.Col ? m.GetCols().ToArray() : m.GetRows().ToArray()));
}
/// <summary>
/// Sorts the given Matrix by the specified row or column selector and returns the new Matrix
/// along with the original indices.
/// </summary>
/// <param name="source">The Matrix</param>
/// <param name="keySelector">Property selector to sort by.</param>
/// <param name="t">Specifies whether to sort horizontally or vertically.</param>
/// <param name="ascending">Determines whether to sort ascending or descending (Default: True)</param>
/// <param name="indices">Vector of <paramref name="t"/> indices in the original Matrix before the sort operation.</param>
/// <returns>New Matrix and Vector of original indices.</returns>
public static Matrix Sort(Matrix source, Func<Vector, double> keySelector, VectorType t, bool ascending, out Vector indices)
{
int max = (t == VectorType.Row ? source.Rows : source.Cols);
indices = Vector.Zeros(max);
List<Vector> vects = new List<Vector>(max);
IEnumerable<Vector> arrays = (t == VectorType.Row ? source.GetRows() : source.GetCols());
KeyValuePair<Vector, int>[] sort = (ascending ?
arrays.Select((i, v) => new KeyValuePair<Vector, int>(i, v))
.OrderBy(o => keySelector(o.Key))
:
arrays.Select((i, v) => new KeyValuePair<Vector, int>(i, v))
.OrderByDescending(o => keySelector(o.Key))).ToArray();
indices = sort.Select(s => s.Value).ToVector();
return sort.Select(s => s.Key).ToMatrix(t);
}
/// <summary>
/// Returns a vector of the median values for each row or column.
/// </summary>
/// <param name="source">Matrix.</param>
/// <param name="t">VectorType.</param>
/// <returns></returns>
public static Vector Median(Matrix source, VectorType t = VectorType.Col)
{
var vectors = (t == VectorType.Row ? source.GetCols() : source.GetRows());
return vectors.Select(s => s.Median()).ToVector();
}
