I need to do chart which shows only markers(anchors). Some x values can have more than one y-value. 
  
  
  
Problem of showing only anchors I has solved using alpha parameter. But, when I was trying to do this using single series line chart, I realized that it doesn't support scale.  
  
For example distance from 1 to 1.1 such as from 1 to 2 on x-Axis. 
  
  
  
How I can set more than one y-value for one x-value?