Texas Instruments TITANIUM TI-89 - Manual (Page 379)

3D Graphing 379
xmin, xmax,
ymin, ymax,
zmin, zmax Boundaries of the viewing cube.
xgrid, ygrid The distance between xmin and xmax and between ymin
and ymax is divided into the specified number of grids. The
z(x,y) equation is evaluated at each grid point where the
grid lines (or grid wires) intersect.
The incremental value along x and y is calculated as:
x increment =
y increment =
The number of grid wires is xgrid + 1 and ygrid + 1. For
example, when xgrid = 14 and ygrid = 14, the xy grid
consists of 225 (15
× 15) grid points.
ncontour The number of contours evenly distributed along the
displayed range of z values.
Variable Description
xmax xmin –
xgrid
---------------------------------
ymax ymin –
ygrid
---------------------------------
z(xmin,ymax) z(xmin,ymin)
z(xmax,ymin) z(xmax,ymax)