public PackedMatrix MultiplyScalar(float val)
{
var r = new PackedMatrix(rowCount, columnCount);
for (int i = 0, len = linearData.Length; i < len; i++)
{
r.linearData[i] = linearData[i] * val;
}
return(r);
}
public void DivideBy(PackedMatrix other)
{
if (rowCount != other.rowCount || columnCount != other.columnCount)
{
throw new Exception("size not match!");
}
for (int i = 0, len = linearData.Length; i < len; i++)
{
//test other.linearData[i] == 0
linearData[i] = Math.Abs(other.linearData[i]) < float.Epsilon ? 1 : linearData[i] / other.linearData[i];
}
}
public void PartialAdd(int centerRow, int centerCol, PackedMatrix other)
{
Matrix.RangeCheck(centerRow, rowCount);
Matrix.RangeCheck(centerCol, columnCount);
var width = other.columnCount;
var height = other.rowCount;
var(startRow, lastRow, otherRowStart) = Matrix.GetRange(centerRow, height, rowCount);
var(startCol, lastCol, otherColStart) = Matrix.GetRange(centerCol, width, columnCount);
for (int i = startRow * columnCount + startCol,
len = lastRow * columnCount + startCol,
k = otherRowStart * width + otherColStart,
delta = lastCol - startCol;
i < len;
i += columnCount, k += width)
{
for (int j = i, updateLen = i + delta, l = k; j < updateLen; ++j, ++l)
{
linearData[j] += other.linearData[l];
}
}
// slow implementation
/*
* for (int i = startRow,k=otherRowStart; i < lastRow; ++k,++i)
* {
* for (int j = startCol,l=otherColStart; j < lastCol; ++l,++j)
* {
* this[i, j] += other[k, l];
* }
* }
*/
}
