The grid plane has integer units, the z axis can be scaled for optimal presentation. Grids can be subsampled for averaging purposes or to speed up the animation of large grids. A number of different colour maps are available. The grid can be drawn as a cylinder or torus if the boundary conditions are appropriate. The radii in both dimensions can be specified.
Files can optionally have a time label, see later.
If a time label is included then it will be displayed as the animation progresses otherwise frame numbers are displayed. The animation can be stopped and single stepped. Note that reverse isn't possible due to the use of an ascii format. Frames can be written to disk at regulat intervals to be assembled later into a stand-alone movie. Single ppm files can be saved at any stage.