void page_center_x()
{
	GraphLayer gl = Project.ActiveLayer();
	if(!gl)
		return;
	
	GraphPage gp = gl.GetPage();
	if(!gp)
		return;
	
	Tree tr;
	tr = gp.GetFormat(FPB_ALL, FOB_ALL, true, true);  // get format tree of the graph page
	//out_tree(tr);  // print this format tree
	
	double dWidth = tr.Root.Dimension.Width.dVal;  // get the width of the graph page
	printf("x center=%f\n", dWidth/2);
}

void page_center_x()
{
	GraphLayer gl = Project.ActiveLayer();
	if(!gl)
		return;
	
	GraphPage gp = gl.GetPage();
	if(!gp)
		return;	

	Tree tr1;
	tr1.Root.Dimension.Units.nVal = 3;  // pixel = 3
	if(0 == gp.UpdateThemeIDs(tr1.Root))
		gp.ApplyFormat(tr1, true, true);  // set unit to pixel

	Tree tr;
	tr = gp.GetFormat(FPB_ALL, FOB_ALL, true, true);  // get format tree of the graph page
	double dWidth = tr.Root.Dimension.Width.dVal;  // get the width of the graph page
	printf("x center=%f\n", dWidth/2);
	
	
	GraphObject go = gl.GraphObjects("TITLE_SAMPLING_RATE");
	go.Text = "sampleString";
	go.Left = dWidth*0.9 - go.Width/2;
}