# CCAD's AutoCAD Tutorials

## Using the @ Symbol

The **@** symbol can be used to input the "last point" in response to any prompt that requests a point value. When combined with a Cartesian or polar coordinate, the **@** symbol produces a point value relative (measured from) the "last point". For example, draw a circle with a radius of 1. Choose the **CIRCLE** command again. When prompted for the **Center point**, type **@** and press **ENTER**. Input a radius of 1.5 for the new circle. The new circle is concentric (having the same center) as the previous circle.

## Relative Cartesian Coordinates

A Relative Cartesian Coordinate specifies an X and Y displacement or movement from the "last point." The coordinate **@2,0** locates a point 2 units along the X axis and 0 units along the Y axis from the "last point." Continuing from the above example, select the **LINE** command. When prompted for the** First point**, type **@3,3** and press **ENTER**. The start of the line is placed 3 units to the right and 3 units up from the "last point" (the center of the circles). Now type** @-6,0** and press **ENTER**. The end of the line is placed 6 units to the left (in the negative X direction) and 0 units up or down from the start of the line, the "last point".

Type **@0,-6** and press **ENTER** and the end of the line will be located 0 units left or right of the "last point" and 6 units below (in the negative Y direction). To complete a square around the two circles, type **@6,0** and press **ENTER**, then right-click and select **Close** from the menu.

## Relative Polar Coordinates

A Relative Polar Coordinate specifies a distance and direction displacement or movement from the "last point". The coordinate **@2<35** locates a point 2 units in the 35° direction from the "last point". To give this a try, select the **LINE** command. When prompted for a **First point:**, click a location anywhere in the drawing area. Type **@2<45** and press **ENTER**. The end of the line is placed 2 units up and to the right of the "last point".

Now type **@4<135** and press **ENTER**. The end of this line is placed 4 units up and to the left of the "last point".

Now type **@2<225** and **ENTER**. This line moves down and to the left from the "last point".

Right-click and select **Close** from the menu.

## Using the Object Snap "Snap From" With the @ Symbol

The **@** symbol is limited to specifying a point relative to the "last point" input. Often it is desirable to choose a point relative to an endpoint, center point or other specific point that is not the "last point" input. Fortunately, there is an **Object Snap** named **From** that allows you to choose a **Base point**. For all practical purposes, this **Base point** becomes the "last point". Try this: Select the **LINE** command. When prompted for the **First point**, type **From** and press **ENTER**. When prompted for the **Base point**, type **Cen** and press **ENTER**. Choose the center of the circles in the Relative Cartesian example above.

Type** @4,4** and press **ENTER**. The start of the line is placed 4 units to the right and 4 units up from the base point. The 8 wide by 8 high box can be completed using the procedure described above.

The **From Object Snap** can be used any time a point needs to be located a certain distance horizontally and vertically from another point. A typical example task is to place four circles inside a box, one near each corner. Select the **CIRCLE** command. When prompted for the **Center point**, type** From** and press **ENTER**. When prompted for the **Base point**, type **End** and press **ENTER**. Select the lower left corner of the inner box. Type **@64;0.625,0.5** and **ENTER**. The point is placed 0.625 units to the right and 1 unit up from the base point. Input a radius of 0.25. Next a circle will be placed near the upper left corner. Select the **CIRCLE** command. When prompted for the **Center point**, type **From** and press **ENTER**. When prompted for the **Base point**, type** End** and press **ENTER**. Select the upper left corner of the inner box. Type **@0.625,-0.5 **and press **ENTER**. The point is placed 0.625 units to the right and 0.5 units down from the base point. Input a radius of 0.25. Try adding the remaining two circles.

The **From Object Snap** can also be used in conjunction with a Relative Polar Coordinate to locate a position a distance and direction from another point. Using the earlier Relative Polar example, select the **CIRCLE** command. When prompted for the **Center point**, type **From** and press **ENTER**. When prompted for the **Base point**, type **Mid** and press **ENTER** . Select the lower right edge of the angled box. Type **@2<135** and press **ENTER**. The point is placed 2 units up and to the left from the base point. Input a radius of 0.5.

Remember, anytime any command prompts you for a point, you can input the **@** symbol to use the "last point", **@X,Y** to indicate a horizontal and vertical movement from the "last point", or **@Dist<Dir** to choose a location at a distance and direction from the "last point".