range rg=[Graph1]Layer1!1;
xlow=xindex１(3.5,rg); //X range from 3.5 to 7.5 properly within the range
xhigh=xindex(7.5,rg); 
mark -st rg -b xlow -e xhigh; //Apply masking
@mp=1;  //0=Show, 1=Hide
mark -u;