Capability analysis in Control Chart builder

[#1]

Dear JMP community,

i am playing a bit with the control chart builder and the capability analysis when I have control limits on the column i am looking at.

I am doing a Levey Jennings control chart, where i hide the moving range since we do not normally look at it - but when i remove the moving range plot the process capability analysis is removed from the output as well.

Is there a way to force it to show a Level Jennings control chart without a moving range plot but still showing the process capability analysis?

I am getting the same issue in both JMP 13.2 and 14.1.

Thanks in advance,

Daniel

[#2 · Accepted solution]

There appears to be a bug.  After I removed the Moving Range Chart, just as you indicated, the Capability Analysis went away.  However, I then clicked off the Spec Limits check box and the Capability Analysis reappeared.  

This needs to be sent to the JMP Support Team @

     support@jmp.com

[#3]

Thanks Jim, I can recreate what you are seeing.

I'll report it - thanks!

/Daniel

[#4]

This is a problem with the software and the developers are working on a correction. Another work around for the problem that allows you to keep both the spec limits and the capability analysis is to turn off the points in the graph (an option in the control panel) and then turn them back on again.

[#5]

Thanks for the confirmation Susan.

Is it possible to click and unclick this button via JSL? I am quite sure that i cannot get my end-users to do it.

But if I could script it, that would be a solution for me.

Thanks,

Daniel

[#6]

I got the following suggestions for workarounds from JMP support which might be able to help someone else as well.

Hi Daniel,

It seems that it is possible to write a script to create the control chart, rather than doing it interactively, and in that case the issue is not encountered. An example follows:

dt = Open("$SAMPLE_DATA/Semiconductor Capability.jmp");
 
rep = dt << Control Chart Builder(
   Show Two Shewhart Charts( 0 ),
   Variables( Y( :NPN1 ) ),
   Chart( Position( 1 ), Limits( Sigma( Moving Range ), Spec Limits( 0 ) ) ),
   SendToReport(
       Dispatch(
           {},
           "NPN1",
           ScaleBox,
           {Add Ref Line( 104.41, "Solid", "Blue", "LSL", 1 ),
           Add Ref Line( 131.89, "Solid", "Blue", "USL", 1 ),
           Add Ref Line( 118.15, "Solid", "Blue", "Target", 1 )}
       )
   )
);

If the user wants to create the chart interactively and then turn the points on and off with a script, that can be done with the following statements:

rep << Chart(Points(Show points (0)));

 

rep << Chart(Points(Show points (1)));

I hope this information is helpful. Please let me know if you or the user have any additional questions.