How to get limits from from column and use it for other columns via JSL?

[#1]

The attached data table has got limits (LSL/USL) for each measured parameter (Current, Resistance) in the respective columns. 

Without changing the data table format, how do I get the limits for each parameter to show as reference lines for example when the Median is plotted vs PartID (as in the script in the attached data table)?

One way I can think of doing this is to save the LSL/USL into the column properties spec limits for each parameter and show them as reference lines, but I need some JSL help for this. This would be my preferred way.

Add Spec Limits () is another option, but I guess, I will need to do this for each measured parameter and  in my actual data (attached is example data) the number of measured parameters is ~50, so this route is not preferable. 

[#2]

Easiest (and in my opinion the best) would be to change the table format but as you cannot do that, then the other options would be using column properties (this would be a bit weird as you would have limits for limits) or graphic script. First you would have to collect all the possible limits for each of the columns (can there be different limits for same columns?), summary should work quite well for this, and then depending on your choice either add then as column properties or use then with graphic script.

[#3]

Here is the way I would handle your table.  It moves all of the USL and LSL values into the column property for each of the columns, and then the limits are automatically displayed when you graph the columns

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

colNamesList = dt << get column names( string, numeric );

For Each( {col}, colNamesList,
	LSL = Column( col )[(dt << get rows where( :Label == "LSL" ))[1]];
	USL = Column( col )[(dt << get rows where( :Label == "USL" ))[1]];
	Eval(
		Substitute(
				Expr(
					Column( col ) << set property(
						"spec limits",
						{LSL( _LSL_ ), USL( _USL_ ), Show Limits( 1 )}
					)
				),
			Expr( _USL_ ), USL,
			Expr( _LSL_ ), LSL
		)
	);

);

// Uncomment the below 2 lines to delete the LSL and USL rows in the table
//dt << select where(:Label == "LSL" | :Label=="LSL");
//dt << delete rows;

Graph Builder(
	Size( 570, 578 ),
	Variables( X( :partID ), Y( :Current ), Y( :Resistance ) ),
	Elements( Position( 1, 1 ), Points( X, Y, Legend( 8 ), Jitter( "None" ) ) ),
	Elements( Position( 1, 2 ), Points( X, Y, Legend( 6 ), Jitter( "None" ) ) ),
	Local Data Filter( Add Filter( columns( :Label ), Where( :Label == {"Median"} ) ) )
);

[#4 · Accepted solution]

@txnelson @jthi 

Thanks, I will try your solution now. I wanted to do something similar but cannot get the following function to work. The idea is to apply this to a column group after grouping all the tested parameter columns. I tried it for one tested parameter (Current) column but it did not work. Works fine when numbers are passed for limits but not when variables are passed. Where did I go wrong (I have tried w & w/o Eval() and Expr()).

Names Default To Here( 1 );

setSpecLimits = Function( {dt_ref, colName, _LSL, _USL},
	{specLimits}, 

	tmp = Eval( Expr( dt_ref:colName << Set Property( "Spec Limits", {LSL( _LSL ), USL( _USL ), Show Limits( 1 )} ) ) );
	Return( specLimits ); //optional
);

////Check
Clear Log();
//test before
specLims = Data Table( "exampleData" ):Current << Get Property( "Spec Limits" ); Show( specLims ); 

//New values
_LSL = Data Table( "exampleData" ):Current[2]; Show( _LSL );
_USL = Data Table( "exampleData" ):Current[3]; Show( _USL );
dt_ref = Data Table( "exampleData" ); show (dt_ref);
colName = "Current"; Show( colName );

//call function
setSpecLimits( dt_ref, colName, _LSL, _USL ); 

//test after
specLims = Data Table( "exampleData" ):Current << Get Property( "Spec Limits" ); Show( specLims ); 

[#5]

Instead of Substitute, you can also use Eval (Eval Expr( ...Exp())):

Eval(EvalExpr(dt_ref:colName << Set Property( "Spec Limits", {LSL(Expr(_LSL )), USL(Expr( _USL) ), Show Limits( 1 )} )))

To pre-evaluate the spec limits _LSL & _USL they have to be inside Expr () and get pre-evaluated via Eval Expr().

After doing so, one can evaluate the whole expression via Eval()

[#6]

This should fix the problem

setSpecLimits = Function( {dt_ref, colName, _LSL, _USL},
	{specLimits}, 

	tmp = Eval(
		eval Expr(
			dt_ref:colName << Set Property( "Spec Limits", {LSL( expr(_LSL) ), USL( expr(_USL ) ), Show Limits( 1 )} )
		)
	);
	Return( specLimits ); //optional
);

[#7]

@txnelson Thanks. Eval Expr () does the trick.

How do I change the spec reference lines to dashed and change dashed line color to say red?

[#8]

You could use the GUI:

[#9]

or JSL:

dt = Open( "$SAMPLE_DATA/Big Class.jmp" );
dt:height << Set Property("Spec Limits",{LSL( 57 ), USL( 67 )});



gb = dt << Graph Builder(
	Variables( X( :height ), Y( :weight ), Overlay( :sex ) ),
	Elements( Points( X, Y, Legend( 1 ) ), Smoother( X, Y, Legend( 2 ) ) ),
);
specs=dt:height << Get Property("Spec Limits");
LSL=specs["LSL"];
USL=specs["USL"];
report(gb)[ScaleBox(1)] <<{	Add Ref Line( LSL, "Dashed", "Red", "LSL", 1 ),
			Add Ref Line( USL, "Dashed", "Red", "USL", 1 )}

[#10]

@hogi  Thanks. I was looking for the JSL way to change solid line to dashed line and default color when the spec limits are defined and saved into column properties and then plotted automatically by JMP (as in post 3 by @txnelson).