codice_23 is an example of one of the many graphics commands included in the Zgrass language. codice_23 requires an X and Y location, as well as a color. In this example, the user supplied codice_25 moves the x position of the curve on the screen, while the Y position is supplied by the trig function, suitably enlarged for display (in this case, 80 times). The color is supplied in the last input, and in this case is 3. The UV-1 used color registers, so 3 did not imply a particular color, but a color selected from the current palette.