/// <summary>
/// Assigns the result of a function to each cell; <i>x[row,col] = function(x[row,col],y[row,col])</i>.
/// <p>
/// <b>Example:</b>
/// <pre>
/// // assign x[row,col] = x[row,col]<sup>y[row,col]</sup>
/// m1 = 2 x 2 matrix
/// 0 1
/// 2 3
///
/// m2 = 2 x 2 matrix
/// 0 2
/// 4 6
///
/// m1.assign(m2, Cern.Jet.Math.Functions.pow);
/// -->
/// m1 == 2 x 2 matrix
/// 1 1
/// 16 729
/// </pre>
/// For further examples, see the <a href="package-summary.html#FunctionObjects">package doc</a>.
/// </summary>
/// <param name="y">the secondary matrix to operate on.</param>
/// <param name="function">a function object taking as first argument the current cell's value of <i>this</i>, and as second argument the current cell's value of <i>y</i>,</param>
/// <returns><i>this</i> (for convenience only).</returns>
/// <exception cref="ArgumentException">if <i>columns() != other.columns() || rows() != other.rows()</i></exception>
/// <see cref="Cern.Jet.Math.Functions"/>
public override ObjectMatrix2D Assign(ObjectMatrix2D y, Cern.Colt.Function.ObjectObjectFunction <Object> function)
{
// overriden for performance only
if (!(y is DenseObjectMatrix2D))
{
return(base.Assign(y, function));
}
DenseObjectMatrix2D other = (DenseObjectMatrix2D)y;
CheckShape(y);
Object[] elems = this.Elements;
Object[] otherElems = other.Elements;
if (elems == null || otherElems == null)
{
throw new NullReferenceException();
}
int cs = this.ColumnStride;
int ocs = other.ColumnStride;
int rs = this.RowStride;
int ors = other.RowStride;
int otherIndex = other.Index(0, 0);
int index = base.Index(0, 0);
// the general case x[i] = f(x[i],y[i])
for (int row = Rows; --row >= 0;)
{
for (int i = index, j = otherIndex, column = Columns; --column >= 0;)
{
elems[i] = function(elems[i], otherElems[j]);
i += cs;
j += ocs;
}
index += rs;
otherIndex += ors;
}
return(this);
}
