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Level II

## How to Get Limits for Capability on IR Control Chart

Hello - How can I read-in spec limits when I check "capability" in the IR chart builder?

Analyze > Quality and Process > Control Chart > IR

I have successfully read-in spec limits when studying process capability (Instructions here:https://community.jmp.com/t5/JMPer-Cable/3-ways-to-load-your-specification-limits-into-Process-Capab...) but it appears to need different input when the data are stacked.

Tim

1 ACCEPTED SOLUTION

Accepted Solutions
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Super User

## Re: How to Get Limits for Capability on IR Control Chart

If you split the data table by the "By" column(s)

Tables==>Split

into separate columns, you can then apply the spec limits independently to each of the new columns by using the

col<<set property("Spec Limits", {USL(xxx),Target(xxx),LSL(xxx)});

Jim
6 REPLIES 6
Highlighted
Staff

## Re: How to Get Limits for Capability on IR Control Chart

You were a bit unclear as to how your specification limits are stored.  You mention that your data is stacked which I assume means you are using a By variable in your analysis.  Below is some general IR  chart code that you can use with a by variable and specification limits.

``````Control Chart(
SendToByGroup( {:Label == "height"} ),
Group Size( 1 ),
KSigma( 3 ),
SendToByGroup(
{:Label == "height"},
Chart Col(
:Data,
Individual Measurement,
Moving Range
),
Capability(LSL(50),Target(60),USL(70));
),
SendToByGroup(
{:Label == "weight"},
Chart Col(
:Data,
Individual Measurement,
Moving Range

),
Capability(LSL(60), Target(70), USL(80))
),
By( :Label )
);``````
Highlighted
Level II

## Re: How to Get Limits for Capability on IR Control Chart

Thank you Tonya.  My spec limits are stored as in their own table (picture attached).

And you are correct, I am using a By variable since data is stacked.  Is there a way to use the "Get Limits" button to pull in the spec limits under this scenario?  It seems with using the code I would still be manually inputting the limits.

Highlighted
Super User

## Re: How to Get Limits for Capability on IR Control Chart

If you split the data table by the "By" column(s)

Tables==>Split

into separate columns, you can then apply the spec limits independently to each of the new columns by using the

col<<set property("Spec Limits", {USL(xxx),Target(xxx),LSL(xxx)});

Jim
Highlighted
Level II

## Re: How to Get Limits for Capability on IR Control Chart

Thank you!  I was mistaken in thinking that data had to be stacked in order to complete the IR.  My data starts split anyway, and this is an ideal solution...thanks for pointing me in the right direction.

Highlighted
Staff

## Re: How to Get Limits for Capability on IR Control Chart

First of all, the Get Limits check box that you are referring to is for Control Limits.  This check box does not have anything to do with Spec Limits and it does not allow you to use a spec limits table.  You can't store your specification limits as column properties since your data is stacked.  Your only option would to be to feed these values in through JSL.  You could use the code I supplied earlier.  Where the spec limits are hard coded in my script, you could refer to specific cells in your spec limits data table.

Highlighted
Level II

## Re: How to Get Limits for Capability on IR Control Chart

That's a helpful clarification, thank you.
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