Cannot set the specification limit attribute (USL/LSL) for each column

[#1]

dt = Current Data Table();

dt << Begin Data Update();
For( i = 9, i <= N Cols( dt ) - 1, i++,
col = Column( dt, i );

// 获取第二行和第三行的数据作为规格限
lowerLimit = col[2];
upperLimit = col[3];
show (lowerLimit);
show(upperLimit); // checked the log, the result is ok.

// 设置规格限属性
col << Set Property( "Spec Limits", {LSL(lowerLimit), USL(upperLimit), Show Limits( 1 )} ); 
);
dt << End Data Update();

[#2]

You will have to evaluate the values to columns, below is an example

Names Default To Here(1); 

dt = Open("$SAMPLE_DATA/Big Class.jmp");

lowlimit = 50;
highlimit = 100;

Eval(EvalExpr(
	Column(dt, "height") << Set Property(
		"Spec Limits",
		{LSL(Expr(lowlimit)), USL(Expr(highlimit)), Show Limits(1)}
	);	
));

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