topic Re: Calculate x sigma Spec Limits for non-normal distribution in Discussions

Calculate x sigma Spec Limits for non-normal distribution

Creatur2 — Wed, 22 Jan 2025 03:52:08 GMT

Currently I need to calculate Non-normal distribution LSL and USL based on sigma value (eg. 4 sigma), to get the process capability.
In another word, I need to select 'Z-score' and 'K:4' and hit the "Calculate Spec Limits" Button automatically in JSL script..
Does anyone know how to use this function in JSL script? Appreciate all kind helps!

Re: Calculate x sigma Spec Limits for non-normal distribution

Ben_BarrIngh — Thu, 23 Jan 2025 11:57:09 GMT

Hi @Creatur2 ,

Could you provide an example dataset and a saved script from the platform onto the data table? I suspect this is from v15 of JMP that you are trying to create?

Thanks,

Ben

Re: Calculate x sigma Spec Limits for non-normal distribution

Creatur2 — Fri, 24 Jan 2025 00:34:56 GMT

Hi Ben,

Thanks for the reply! I am using JMP 17 Pro.

I attached the example file contains fake data and saved a distribution script to Data Table.

The problem is that, I want it to calculate K-sigma Limit automatically in the script, like the line of LSL and USL here should be something like 'Use Column 4-sigma Specs'. But saved script is actually recording the number but not the calculation steps.

Re: Calculate x sigma Spec Limits for non-normal distribution

Ben_BarrIngh — Fri, 24 Jan 2025 09:37:17 GMT

Hi @Creatur2 ,

Here's the script for performing the K sigma multiplier 'in script' - you can find details in the Scripting Index (see screenshot below).

Distribution(
	Stack( 1 ),
	Continuous Distribution(
		Column( :Example ),
		Horizontal Layout( 1 ),
		Vertical( 0 ),
		Fit Normal 3 Mixture(
			Process Capability(
			Set Sigma Multiplier for Quantile Spec Limits(
			4),
				Show as Graph Reference Lines,
				Nonnormal Capability Method( "Z-Score"n )
			)
		),
	),
	SendToReport(
		Dispatch( {"Example"}, "1", ScaleBox,
			{Add Ref Line( 2.20020487561508, "Solid", "Blue", "LSL", 1 ),
			Add Ref Line( 4.81371452626116, "Solid", "Blue", "USL", 1 )}
		)
	)
);

Re: Calculate x sigma Spec Limits for non-normal distribution

Creatur2 — Sun, 09 Feb 2025 15:17:59 GMT

Hi Ben,

Thank you so much! This problem have been confused me for at least 1 month. Really appreciate your help!!!