How to label the curve with its degree of curvature (Da)?

[JamaL9722060]

How to label the curve with its degree of curvature (Da)?

Degree of curvature (Da) can be calculated based on two different ways

Arc definition (considering 30 meters arc length):

Da=1719.74/R

Chord definition (considering 30 meters chord length):

Da=ASIN(50/Radius)*2

The issue here is that there is not built in option to label the curve with its degree of curvature

How this might be accomplished?

Thank you

Best

Jamal

[Jeff_M]

Create expressions, as you have read in other posts. Under the General Curve Labels and/or the Alignment curve labels create an expression for the type of DoC label you wish to use:

Then use the exprssion in the label style:

[Jeff_M]

Actually, it looks like your Chord formula is for a 100 unit chord, so append *0.30 to the end of the chord expression. The Arc definition expression looks suspect as well....

[Jeff_M]

This is the expression needed for a 100 unit arc length:

DEG2RAD(5729.58/{General Segment Curve Radius})

Multiply the 5729.58 by 0.30 for a 30 unit arc length

[JamaL9722060]

Many thanks Jeff for the help. Very much appreciated for the screenshots.

I couldn’t find “General segment curve radius”.

Please, have a look on the attached screenshots. Am I in the correct place?

[Jeff_M]

The one I showed was for the General Curve label style expressions. For the Alignment, use the Radius property for the curve. PI's don't necessarily define a curve so you won't be able to include curve information in a PI label, must use a curve label.

[JamaL9722060]

Thank you Jeff for the prompt help,

I’ve created a style and labeled with it but sounds that the result is not correct.

The expected value is assumed to be 1719.74/R. R is given as 66.7 while 1719.74/66.7 is supposed to be 26.

When labeling, the angle is as shown in the attached screenshots

What might be the issue then?

[Jeff_M]

Look back at message number 4 that I posted. In the Expression, the returned value must be converted from Degrees to Radians, as C3D's labels use Radians and then converts it to whatever format you want displayed.

[BrianHailey · Accepted solution]

Just add the degree of curvature to your label. It's a standard property now.

If you want to change the length used in the calculation, it's in your drawing/feature/command settings.

[Jeff_M]

Now why didn't I see that in one of Jamal's images??? Guess I need to spend more time with the newer version(s).

[JamaL9722060]

Many thanks Brian for the help. This is great that this property is built in (attached). Many thanks Jeff for the massive support. Best Jamal

[yvesbc6]

May I know what is the difference between setting the length of the chord to 30m. and 20m.?

[BrianHailey]

Taken from the Wikipedia entry for Degree of Curvature: