public ImmutableDenseMatrix <TDataType, TOperationDefiner> Subtract(
ImmutableDenseMatrix <TDataType, TOperationDefiner> addend)
{
if (!SameSize(addend))
{
throw new ArgumentOutOfRangeException(nameof(addend),
(addend), "Addend must be same size as the matrix");
}
var items = addend.Items;
var itemCount = ItemCount;
var array = new TDataType[itemCount];
for (int i = 0; i < itemCount; i++)
{
array[i] = _opDef.Add(Items[i], _opDef.Negative(items[i]));
}
return(new ImmutableDenseMatrix <TDataType, TOperationDefiner>(array.UnsafeMakeImmutable(), RowCount, ColumnCount));
}
public bool Equals(ImmutableDenseMatrix <TDataType, TOperationDefiner> equand)
{
if (equand == null)
{
return(false);
}
if (!SameSize(equand))
{
return(false);
}
var items = equand.Items;
for (int i = 0; i < ItemCount; i++)
{
if (!_opDef.Equals(Items[i], items[i]))
{
return(false);
}
}
return(true);
}
public ImmutableDenseMatrix <TDataType, TOperationDefiner> Multiply(ImmutableDenseMatrix <TDataType, TOperationDefiner> multiplicand)
{
if (!CanMultiply(multiplicand))
{
throw new ArgumentOutOfRangeException(nameof(multiplicand),
(multiplicand), "Multiplicand must have the same number of rows as the matrix has columns");
}
var thatItems = multiplicand.Items;
var array = new TDataType[RowCount * multiplicand.ColumnCount];
var zero = _opDef.Zero;
var columnCount = ColumnCount;
var rowCount = RowCount;
var thatColumnCount = multiplicand.ColumnCount;
var resultPointer = 0;
for (int i = 0; i < rowCount; i++)
{
for (int j = 0; j < thatColumnCount; j++, resultPointer++)
{
var thisPointer = columnCount * i;
var thatPointer = j;
var sum = zero;
for (int k = 0; k < columnCount; k++, thisPointer++, thatPointer += thatColumnCount)
{
sum = _opDef.Add(sum, _opDef.Multiply(Items[thisPointer], thatItems[thatPointer]));
}
array[resultPointer] = sum;
}
}
return(new ImmutableDenseMatrix <TDataType, TOperationDefiner>(array.UnsafeMakeImmutable(), rowCount, thatColumnCount));
}
