double wks_cell(Worksheet & wks, int nr, int nc)
{
	double vv = NANUM;
	if(nr < 0 || nr >= wks.GetNumRows() || nc < 0 || nc >= wks.GetNumCols())
		return vv;
	
	try {
		vv = wks.Cell(nr, nc);
	}
	catch(int nErr)
	{
		// put codes here if err handling is needed
	}
	
	return vv;
}

void test_check_wks_missing()
{
	Worksheet wks = Project.ActiveLayer();
	
	for(int ii = 0; ii < wks.GetNumCols(); ii++)
	{
		for(int jj = 0; jj < wks.GetNumRows(); jj++)
		{
			double vv = wks_cell(wks, jj, ii);//wks.Cell(jj, ii);
			if(is_missing_value(vv) || vv < 2)
			{
				string str = wks.TCell(jj, ii);
				printf("Cell(%d,%d) is no good, it is \"%s\"\n", jj, ii, str);
			}
		}
	}
}