### 17.4 Plot Annotations

— Function File: grid (arg)

> For two-dimensional plotting, force the display of a grid on the plot. The argument may be either `"on"` or `"off"`. If it is omitted, `"on"` is assumed.

— Function File: title (string)

> Specify a title for a plot.

— Function File: xlabel (string)
— Function File: ylabel (string)
— Function File: zlabel (string)

> Specify x, y, and z axis labels for the plot. If you already have a plot displayed, use the command `replot` to redisplay it with the new labels.

— Function File: top_title (string)
— Function File: bottom_title (string)

> Makes a title with text string at the top (bottom) of the plot.