Creating Spec limits

[#1]

Hi, 

I'm trying to create spec limits using jmp interface or jsl. I'm trying to create the spec limit for different columns with no USL or LSL.. Please help. thank.

[#2]

Have you looking into the Limits Manager?

     Analyze=>Quality and Process=>Limits Manager

[#3]

Hi Jim, 

I have looked at it, but from what I see this tool is to accept limit and apply it to column. What I'm trying to do is to make just calculate a USL or LSL based on a sigma, and a mean that I provide. Or if there is a tool where I specific what I want the sigma to be for that column and then JMP generates the spec limits. Have you been across something like this ? thanks Jim.

[#4 · Accepted solution]

Spec Limits are not normally calculated limits.  They are set based on the design specifications or on the tool limitations, etc.

However, here is a simple script that will set the spec limits for all continuous columns in a data table using 3 sigma limits

Names Default To Here( 1 );
dt = Current Data Table();

colNames = dt << get column names( string, continuous );

For Each( {col}, colNames,
	theMean = Col Mean( As Column( dt, col ) );
	theSTD = Col Std Dev( As Column( dt, col ) );
	Eval(
		Substitute(
				Expr(
					Column( dt, col ) << set property(
						"Spec Limits",
						{LSL( _LSL_ ), Target( _Target_ ), USL( _USL_ ), Show Limits( 1 )}
					)
				),
			Expr( _LSL_ ), theMean - 3 * theSTD,
			Expr( _Target_ ), theMean,
			Expr( _USL_ ), theMean + 3 * theSTD
		)
	);
);

[#5]

Certainly! To create spec limits in JMP using JSL, open your data table, choose the desired column, and use the Distribution platform with the Spec Limits option to set your limits.