Limits that change (shift) over time

Question

Hi all,

User of JMP 18.

To trend our processes, we may use up to 4 different sets of limits:

* upper/lower alert limits UAL/LAL
* upper/lower action limits UACL/LACL
* upper/lower control limits UCL/LCL
* upper/lower specification limits USL/LSL

In theory they could all exist and be applied for a given parameter, and they could shift over time due to some change to the process - so suddenly from batch to another.

I'm wondering how I can easily visualize this using Control Chart Builder and Graph Builder. Do I need JSL? Can I rely on Column Properties alone?
Any tips and tricks are welcome, or referals to similar threads.

Thanks!

Guy

txnelson · Answer

You will need to use JSL to accomplish what you want given your data table and limit table you specified.  I envision that one would create the given chart and then loop through the limits in the limit table and create  matrices that represent the start and stop points for the line for each limit.  Finally, then using Add Graphics Script, use the Line() function for each matrix to display each of the lines.

guyvanhove · Answer

Actually, I would like to store the limits in a separate table, like this:

Parameter NameLSLUSLLACLUACLLALUALLCLUCLEffective DateParameter x5080  657060751-jan-22Parameter x5580  657060751-jul-22Parameter y   100  40801-jan-22Parameter y  10100  408012-sep-24Parameter y 12010100  40805-dec-25

The actual data I'd like to trend is in a separate, big table, like this. The parameter names in both tables correspond.

BatchManufacturing DateParameter xParameter yA1-jan-216156B10-jan-2162102C21-jan-215357D31-jan-217488............

hogi · Answer

spec limits could change if a user requires a tighter spec.
rare - but not 100% excluded.

Maybe so rare that it's not worth to implement the case in the software.