Method that creates a new Arc2d object. The object created is a transient mathematical object and is not displayed graphically.
| Name | Type | Description |
| Center | Point2d | Input Point2d object that specifies the center of the arc. Length units are always centimeters. |
| Radius | Double | Input Double that specifies the radius of the arc. |
| StartAngle | Double | Input Double that specifies the start angle of the arc. An angle of 0 is along the positive X axis of the sketch plane. |
| SweepAngle | Double | Input Double that specifies the sweep angle of the arc. The sweep direction is always counterclockwise. |