This situation commonly occurs if the result of the calculation is only 1 datum point. It is not possible for the EMGworks graph tools to plot only 1 datum point, since at least 2 points are required to draw a line. The single datum point can be easily viewed by using the “gridview” feature in the “view “menu. Note that versions of EMGworks 3.6 and higher will display the X and Y coordinates of the datum point on the plot area.