Define axes characteristics. AXIS1 uses
ORDER= to set major tick marks at 2-unit intervals from -10 to -4. AXIS2 uses
ORDER= to specify 2-unit intervals from -10 to 2. These axes ranges effectively
zoom in on one of the contour areas from
Generating a Simple Contour Plot.
axis1 order=(-10 to -4 by 2);
axis2 order=(-10 to 2 by 2);