2 Replies Latest reply on Sep 25, 2013 2:59 PM by Brent Daniel

    Applying Color or Labels to only one line (P-Chart with Variable Control Limits)

    Brent Daniel

      I'm trying to render some data in a P-Chart (a type of control chart) with variable control limits (control limits governed by n). Where I'm stuck is in applying the control tests (that label points that are out of control) AND having the variable control limits on the same graph.

       

      (I've leveraged the Run Chart example in http://dataremixed.com/2011/10/how-to-make-control-charts-with-tableau/, which got be pretty far.)

       

      First, I am able to do everything I want, so long as I use Reference Lines for the Control Limits. Unfortunately, the reference lines take the average of the variable control limits, so they will fail to be useful when the sample size varies a lot.

       

      AvgCL.JPG.jpg

       

      And, I am able to render the variable control limits by creating overlapping graphs:

       

      VariableCL.JPG.jpg

       

      The thing is, if I apply the "Label" to this graph, I get labels both on the data line (blue) and on the control limit lines (red). Like so:

      VariableCL labelled.JPG.jpg

       

      Does anyone have any ideas so I can get the best of both graphs?  I either need to have a variable reference line (not possible?), or apply the labels (and colors, perhaps) to just the blue line.