# 3.5 Editing items on the canvas

All objects on a multiplot canvas have a unique identification number. By default, these count up from one, such that the first item placed on the canvas is number one, the next is number two, and so forth. Alternatively, the user may specify a particular number for a particular object by supplying the modifier `item` to the `plot` command, followed by an integer identification number, as in the following example:

    plot item 6 'data.dat'

If there were already an object on the canvas with identification number 6, this object would be deleted and replaced with the new object.

A list of all of the objects on the current multiplot canvas can be obtained using the `list` command, which produces output in the following format:

    # ID   Command
        1  plot item 1 'data1.dat'
        2  plot item 2 'data2.dat'
        3  [deleted] plot item 3 'data3.dat'

A multiplot canvas can be wiped clean by issuing the `clear` command, which removes all items currently on the canvas. Alternatively, individual items may be removed using the `delete` command, which should be followed by a comma-separated list of the identification numbers of the objects to be deleted. Deleted items may be restored using the `undelete` command, which likewise takes a comma-separated list of the identification numbers of the objects to be restored, e.g.:

    delete 1,2
    undelete 2

Once a canvas has been cleared using the `clear` command, however, there is no way to restore it. Objects may be moved around on the canvas using the `move` command. For example, the following would move item 23 to position measured in inches:

    move 23 to 8*unit(in), 8*unit(in)

- 3.5.1 Settings associated with multiplot items
- 3.5.2 Reordering multiplot items
- 3.5.3 The construction of large multiplots