Handling Conditional Display of Y-Axis Variables in JSL for Graph Building

[#1]

When using `graph built`, how can I describe the requirement in JSL that certain Y-axis variables, which may not always appear, should be displayed if they have values and not displayed if they have no values? The following two methods have not been effective.

1.

dt = Open("$SAMPLE_DATA/Big Class.jmp");
Graph Builder(
	Size( 534, 450 ),
	Show Control Panel( 0 ),
	Variables( X( :sex ), try(Y( :bbb )), Y( :height ), Y( :weight ) ),
	Elements( Position( 1, 1 ), Points( X, Y, Legend( 13 ) ) ),
	Elements( Position( 1, 2 ), Points( X, Y, Legend( 14 ) ) ),
	Elements( Position( 1, 3 ), Points( X, Y, Legend( 15 ) ) )
);

2.

dt = Open("$SAMPLE_DATA/Big Class.jmp");
Graph Builder(
	Size( 534, 450 ),
	Show Control Panel( 0 ),
	Variables( X( :sex ), Y( :bbb ), Y( :height ), Y( :weight ) ),
	Elements( Position( 1, 1 ), Points( X, Y, Legend( 13 ) ) ),
	Elements( Position( 1, 2 ), Points( X, Y, Legend( 14 ) ) ),
	Elements( Position( 1, 3 ), Points( X, Y, Legend( 15 ) ) )
);

[#2]

Hi @BabyDoragon, is bbb a column that either exists or not and this is what we need to check, or bbb is always there but some values(rows) are missing ?

[#3]

The default value of bbb is {}, and sometimes it may be stored as a variable, for example in the following two cases.

1.

dt = Open("$SAMPLE_DATA/Big Class.jmp");
bbb={};
bbb="age";
Graph Builder(
	Size( 534, 450 ),
	Show Control Panel( 0 ),
	Variables( X( :sex ), Y( as column(bbb)), Y( :height ), Y( :weight ) ),
	Elements( Position( 1, 1 ), Points( X, Y, Legend( 13 ) ) ),
	Elements( Position( 1, 2 ), Points( X, Y, Legend( 14 ) ) ),
	Elements( Position( 1, 3 ), Points( X, Y, Legend( 15 ) ) )
);

2.

dt = Open("$SAMPLE_DATA/Big Class.jmp");
bbb={};
//bbb="age";
Graph Builder(
	Size( 534, 450 ),
	Show Control Panel( 0 ),
	Variables( X( :sex ), Y( as column(bbb)), Y( :height ), Y( :weight ) ),
	Elements( Position( 1, 1 ), Points( X, Y, Legend( 13 ) ) ),
	Elements( Position( 1, 2 ), Points( X, Y, Legend( 14 ) ) ),
	Elements( Position( 1, 3 ), Points( X, Y, Legend( 15 ) ) )
);

I hope to enable the graph to automatically include or exclude this item based on whether there are any variables currently in bbb.

[#4 · Accepted solution]

You can build the expression or add variable later

Names Default To Here(1);
dt = Open("$SAMPLE_DATA/Big Class.jmp");
gb = dt << Graph Builder(
	Size(534, 450),
	Show Control Panel(0),
	Variables(X(:sex), Y(:height), Y(:weight)),
	Elements(Position(1, 1), Points(X, Y, Legend(13))),
	Elements(Position(1, 2), Points(X, Y, Legend(14)))
);
dt << new column("A", Numeric, Continuous, Formula(Row()));

extra_cols = {"height", "A"};

For Each({extra_col}, extra_cols,
	Eval(EvalExpr(
		gb << Add Variable({Expr(NameExpr(AsColumn(dt, extra_col))), Role("Y")});
	));
);

Depending on what you are trying to do, there can be quite a few things to take into account (order, type of plots, legend, ...)

If I remember correctly this might have something related to this topic Scripters Club Recording: JSL in Graph Builder