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Capability calculations for True Position

Has anyone come across this as a means of calculating Cpk of a true position?

http://documentation.statsoft.com/ST...tionCapability

I think it should be possible, but I'm not sure if this is the answer or not. I was thinking about how something along the lines of the complex plane (or vectors/trig) could be used to identify grouping of a positional tolerance based on its quadrant within a unit circle, and then could be used to calculate Cpk. It's not unheard of. The normal distribution of a multivariate system is calculable, so why wouldn't a statistic that is related to the normal distribution in 1 variable work for higher dimensions?

I'm thinking that there must be a way to calculate the variance of position based on the the quadrant it falls in. Whether it's a trigonometric function, or a complex function.

Anyone have any input as I dive into this blackhole?

Curiosity killed the cat, hopefully I'm not a cat.

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  • : you're welcome !
    It was funny to do it on sunday morning while everybody was sleeping at home Wink
    Can you just tell me if the sub "macro" works, and the functions, from french to english (I don't know how to change the language Disappointed ! )
  • Which macro? I'm playing around with the file from this post, and all of the calculations seems to work. Some of them are a bit above my head, so I'm trying to work through exactly what is happening in each call, but it's working great from what I can tell.

    My only question would be on the final calculations, there are just numbers in those cells, so there's no indication of what is being calculated for Cp/Cpk1/Cpk2. I think that the calculation is not the standard Cpk calculation, so I'm not sure how to double check those. I like the addition of the line chart that changes with the change in angle. Very professional. Slight smile

    Kudos to you for doing this on a Sunday morning too. Super Jefman to the rescue.