How to have different reference line by groups in variability charts?

alvin

I am trying to add different reference lines based on groups in a variability chart, but there seem to be no straight forward way to do it.

I have different targets based on the groups and a column has the target data already in there.

How to make use of the available target column data and draw reference lines based on the different groups?

ian_jmp

Is this the kind of plot you are after?

If so, for the Variability Chart you will need to use a graphics script. You can make the plot above by running this script:

Names Default To Here(1);

dt = Open("$SAMPLE_DATA/Big Class.jmp");
dt << Variability Chart(
			Y( :height ),
			X( :sex ),
			Std Dev Chart( 0 ),
			SendToReport(
				Dispatch(
					{"Variability Chart for height"},
					"Variability Chart",
					FrameBox,
					{Add Graphics Script(
						2,
						Description( "" ),
						Pen Color( "Red" );
						// Females
						H Line( 0, 1, 55 );
						H Line( 0, 1, 65 );
						// Males
						H Line( 1, 2, 52 );
						H Line( 1, 2, 67 );
					)}
					)
				)
			);

To add horizontal lines by hand, do a right click on the white area of the graph and select 'Customize...'. Then hit the '+' sign to add them using 'HLine()' with the values you need:

You can add such lines as part of a bigger JSL script, and if you need to do this often you may want to look into this.