Specifying Axis Options

To set axis options on the LAYOUT OVERLAY statement, you use the following syntax. Notice that each axis has its own separate set of options, and that the option specifications must be enclosed in parentheses. GTL frequently uses parentheses to bundle options that modify a specific feature. These are called "option bundles."

layout overlay / xaxisopts =(options) yaxisopts =(options) 
  x2axisopts=(options) y2axisopts=(options);

If you specify the X2AXISOPTS= or Y2AXISOPTS= options but there is no data mapped to these axes, the option bundles are ignored.

One of the basic options that you can set for any axis is DISPLAY= keyword | ( feature-list ). Four features are available for the feature-list: LINE, TICKS, TICKVALUES, and LABEL. The keywords STANDARD and ALL are equivalent to specifying the full list: ( LINE TICKS TICKVALUES LABEL ). You can also use DISPLAY=NONE to completely suppress all parts of the axis.

Example: Some plots don't really need TICKS on all axes. The follow axis option eliminates the ticks on the X axis by omitting the TICKS value on the feature-list.

layout overlay / xaxisopts=( display=( line label tickvalues )  );
  barchartparm x=city y=fahrenheit; 
endlayout;

Let's return to the common situation where you want a duplicated Y2 axis. Here is the most efficient way to do it:

layout overlay / yaxisopts=( displaysecondary=standard );
  barchartparm x=city y=fahrenheit; 
endlayout;

This specification creates the Y2 axis as a duplicate of the Y axis: all features are displayed without having to map data to the Y2 axis. You can also restrict the secondary axis features that are displayed by specifying a list of the features you want to be displayed. The values available for the DISPLAYSECONDARY= option are the same as those of the DISPLAY= option. The following example specifies that the secondary axis label will not be displayed. It also requests that grid lines be displayed on the Y axis:

layout overlay / xaxisopts=( display=( line label tickvalues ) )
    yaxisopts=( displaysecondary=( ticks tickvalues line )
      griddisplay=on );
  barchartparm x=city y=fahrenheit; 
endlayout;