Hi Dale,

This is a python code from:

http://developer.rhino3d.com/api/RhinoCommon/html/M_Rhino_Geometry_LinearDimension__ctor_1.htm

```
import Rhino
import scriptcontext
import System.Guid
def AddLinearDimension2():
origin = Rhino.Geometry.Point3d(1,1,0)
offset = Rhino.Geometry.Point3d(11,1,0)
pt = Rhino.Geometry.Point3d((offset.X-origin.X)/2.0,3,0)
plane = Rhino.Geometry.Plane.WorldXY
plane.Origin = origin
rc, u, v = plane.ClosestParameter(origin)
ext1 = Rhino.Geometry.Point2d(u,v)
rc, u, v = plane.ClosestParameter(offset)
ext2 = Rhino.Geometry.Point2d(u,v)
rc, u, v = plane.ClosestParameter(pt)
linePt = Rhino.Geometry.Point2d(u,v)
dimension = Rhino.Geometry.LinearDimension(plane, ext1, ext2, linePt)
if scriptcontext.doc.Objects.AddLinearDimension(dimension)!=System.Guid.Empty:
scriptcontext.doc.Views.Redraw()
return Rhino.Commands.Result.Success
return Rhino.Commands.Result.Failure
if __name__=="__main__":
AddLinearDimension2()
```

The generated dimension has properties below:

```
Geometry:
Linear dimension (rotated)
Measurement: 0.00000 millimeters
Text: Plane: Origin: (1,1,0) X: (1,0,0) Y: (0,1,0) Z: (0,0,1)
First point: (1,1,0), Second point: (-1.23432e+308,-1.23432e+308,0)
Text point: (-6.17161e+307,-1.23432e+308,0) (Default)
Text rotation: 0 degrees
```