* @param A matrix operator
* @return CoordinateTransformation which performs <A, b> = x
*/
public ICoordinateTransform linear_operator(final IDoubleArray A) {
int rows = A.rows(), cols = 1;
return new AbstractCoordinateTransform(rows, cols)
{
@Override
public void transform(final IDoubleArray in, IDoubleArray out)
{
IDoubleArray input = in;