Comparison of drawing and stretching, interrupting and decomposing commands in AutoCAD

Here are two sets of easily confusing modification commands. Of these four commands, in addition to the explode (explode) command, the other three commands must start the command when used, and then select the object to edit.

5.4.1 Stretch (extrude) command

When you use the Extrude command, you must select the object in the form of a cross polygon or a cross window. If you select all of the objects, the command is equivalent to the move command. If some of the objects are selected, the stretch command moves only the endpoints of the objects within the selection, while the other endpoints remain unchanged (see Figure 5-34). The objects available for the "Stretch" command include arcs, elliptical arcs, straight lines, multi-line line segments, rays, and spline curves.

The command is invoked in the following ways:

Toolbar: "Modify (modified)" →

Menu: "Modify (modified)" → "Stretch (stretching)"

Command line: Stretch (or alias s)

When this command is invoked, the system prompts the user to select the object by means of a cross window or a polygon:

Select objects to stretch by Crossing-window or crossing-polygon ...

Select objects:

The user is then prompted for a move operation, which is the same as the "Moves" command:

Specify base point or displacement:

Specify second point of displacement or <use as Displacement>:

5.4.2 Lengthen (elongated) command

The elongated command is used to change the angle of the arc, or to change the length of the closed object, including lines, arcs, closed multiple lines, elliptical arcs and closed spline curves.

The command is invoked in the following ways:

Toolbar: "Modify (modified)" →

Menu: "Modify (modified)" → "Lengthen (elongated)"

Command line: Lengthen (or alias Len)

When this command is invoked, the user is prompted to select the object:

Select an object or [delta/percent/total/dynamic]:

When the user selects an object, the system displays the length of the object, and if the object has a corner that contains the angle:

Current length:, included angle:

Other options give you four ways to change the length or angle of an object (see Figure 5-35).

(1) Delta (Delta): Specifies a length or angle increment, and further prompts the user to select an object:

Enter Delta length or [Angle] <0.0000>:

Select an object to change or [Undo]:

If the user-specified increment is positive, the object increases an increment length (angle) from the closest endpoint of the distance selection point, and if the user-specified increment is negative, the object shortens an increment length (angle) from the endpoint closest to the distance selection point.

(2) "Percent (%)": Specifies the percentage of the total length or total angle of the object to change the length or angle of the object, and further prompts the user to select the object:

Enter percentage length <100.0000>:

Select an object to change or [Undo]:

If the user specifies a percentage greater than 100, the object extends from the closest endpoint of the distance selection point, the length (angle) of the extension to the original length (angle) multiplied by the specified percentage, and if the user specifies a percentage less than 100, the object is trimmed from the nearest endpoint of the distance selection point. The length (angle) of the trim is multiplied by the specified percentage for the original length (angle).