There are vi's available to read mouse position. Look for mouse in the example code section here. You can use the Position attribute of the property node of your graph to get the mouse position within the graph. You can get the range of the scales from the property node. Then it will be a bit of straightforward math to figure out the values. Beware that the size of the drawing area of the graph can change as the numbers in the scales get bigger or smaller! Good Luck
Thanks, i got it. i insert a image and get the posittion mouse and i put the reference with the scales max and min from the porperty node... it works!!