Use the DELETE command to delete elements from a picture. First, press the command letter, then select the element to delete as follows. Position the cross-hair cursor near the element you want to delete and press RETURN. PEP finds the nearest picture element and displays a box around it. (The element is also displayed in the preview window.) You can accept this choice or reject it. Press RETURN to accept, or SPACE to reject. If you accept the choice, the boxed element is deleted and the cross-hair reappears. You are now ready to delete another element. However, if you press SPACE to reject the boxed element, the next closest element is selected. Once again, you can press either RETURN to delete the boxed element or SPACE to select another. By repeatedly pressing SPACE, you can step through every element in the picture, if necessary, to select the one you wish to delete. The example <[FIG26]> shows a picture containing two elements: a circle object and a straight line. At the first stage, the delete command has been executed and the cross-hair cursor has been positioned. Then if you press RETURN, a box is displayed abound the nearest element (the circle). Pressing RETURN again deletes the circle and re-displays the cross-hair. However, pressing SPACE instead encloses the next element (the line) in a box. Now pressing RETURN deletes the line. There is also a DELETE command in the COLLECT menu, which may be more convenient if you are deleting multiple elements. For example, if you want to delete all text labels, the easiest way is first to collect them all and then use the COLLECT/DELETE command <[5.9]>. For more information on this technique, see Chapter <[5]>.

The UN-DELETE command re-inserts the most recently deleted element, at its former location. If you press the command letter a second time, the next most recently deleted element will be restored. If you continue to execute the command, more items will be re-inserted. The order in which they are restored is the opposite of the order in which they were deleted. Un-deleting is possible because a record is kept of every deletion. This record is called the un-delete queue. The number of elements remembered is limited only by the available memory. However, the FILE/LOAD <[8.2]>, FILE/NEW <[8.1]>, and OBJECT/ELIMINATE <[7.6]> commands clear the queue of deleted elements.