Specifying Coordinates

All drawings are based on a Cartesian coordinate system in which three perpendicular axes are used: the X, Y, and Z. All axes originate in the origin point of the coordinate system. The X-axis and Y-axis define a horizontal plane. The X-axis and Z-axis, as well as the Y-axis and Z-axis, define vertical planes.

In the Cartesian coordinate format, a point is defined by its distances to the XY-, XZ- and YZ-planes. These distances are called the XYZ-coordinates of a point. When you draw in 2D, you specify points only on the XY-plane. The Z-coordinate is omitted. In CAD, the fixed Cartesion coordinate system is called the World Coordinate System (WCS). New drawings are based on the WCS.

Enter coordinates as absolute or relative values. To specify the point coordinates with respect to the previous point (relative coordinate input), type the "@" character in front of the coordinate values.

Absolute Coordinates

Type of Coordinate Input Example
Cartesian (2D / 3D) X,Y  /  X,Y,Z 3.5,8.2,6.7
Polar (2D) distance<angle 7.5<45
Cylindrical (3D) distance<angle,Z-coordinate 7.5<45,12.2
Spherical (3D) distance<angle1<angle2 7.5<45<33

Relative Coordinates

Type of Coordinate Input Example
Cartesian (2D / 3D) @deltaX,deltaY  /  @deltaX,deltaY,deltaZ @3.5,8.2,6.7
Polar (2D) @relative_distance<angle @7.5<45
Cylindrical (3D) @relative_distance<angle,Z-coordinate @7.5<45,12.2
Spherical (3D) @relative_distance<angle1<angle2 @7.5<45<33

To specify absolute Cartesian coordinates:

  1. Enter a command requiring coordinates, for example Line.
  2. Specify the X-, Y- and Z-coordinates separated by commas, for example 0,0,0.
  3. Specify subsequent coordinates to complete the command, for example 3.5,8.2,6.7.

    To place a point in the XY-plane (Z coordinate is zero), omit the Z-coordinate. For example, type 3.5,8.2.

To specify relative Cartesian coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0,0.
  3. To specify the second point with respect to the first point, type the "@" character in front of the coordinate values: @3.5,8.2,6.7.

To specify absolute polar coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0.
  3. Specify the second point using the 2D format, "distance<alpha_angle", for example 7.5<45.

    distance: Specifies the distance from the origin

    alpha_angle: Specifies the angle in the XY-plane (positive angles are measured counter-clockwise)

To specify relative polar coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0.
  3. Specify the second point with respect to the first point using the 2D format, "@distance<alpha_angle", for example @7.5<45.

To specify absolute cylindrical coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0,0.
  3. Specify the second point using the 3D format, "distance<alpha_angle,z_coordinate", for example 7.5<45,12.2.

    distance: Specifies the distance from the origin

    alpha_angle: Specifies the angle in the XY-plane (positive angles are measured counter-clockwise)

    z_coordinate: Specifies the height above the XY-plane

To specify relative cylindrical coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0,0.
  3. Specify the second point with respect to the first point using the 3Dl format, "@distance<alpha_angle,z_coordinate", for example @7.5<45,12.2.

To specify absolute spherical coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0,0.
  3. Specify the second point using the 3D format, "distance<alpha_angle<beta_angle", for example 7.5<45<33.

    distance: Specifies the distance from the origin

    alpha_angle: Specifies the angle in the XY-plane (positive angles are measured counter-clockwise)

    beta_angle: Specifies the angle measured from the XY-plane (positive angles are measured above the XY-plane)

To specify relative spherical coordinates:

  1. Enter a command requiring coordinates.
  2. Specify the first point, for example 0,0,0.
  3. Specify the second point with respect to the first point using the 3D format, "@distance<alpha_angle<beta_angle", for example @7.5<45<33.

Command Sequence

To specify absolute Cartesian coordinates:

: Line
Specify start point» 0,0,0
Specify next point» 3.5,8.2,6.7
...

To specify relative Cartesian coordinates:

: Line
Specify start point» 0,0,0
Specify next point» @3.5,8.2,6.7
...

Related Topics

Coordinate Input and Coordinate Systems

Specifying Points Using Coordinate Filters